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Dell PowerScale (Isilon) vs IBM FlashSystem vs NetApp FAS Series comparison

 

Comparison Buyer's Guide

Executive Summary

Review summaries and opinions

We asked business professionals to review the solutions they use. Here are some excerpts of what they said:
 

ROI

Sentiment score
6.2
Organizations benefit from Dell PowerScale's efficiency, scalability, cost savings, improved performance, and reliable data management without extra staffing.
Sentiment score
6.3
IBM FlashSystem offers high ROI with efficient migration, scalability, and performance, despite post-acquisition price increases; valued for reliability.
Sentiment score
5.5
NetApp FAS Series users report positive ROI, cost savings, and satisfaction, especially in VMware settings, despite disk addition expenses.
Despite being more expensive than Huawei, it is stable and most enterprises accept the price due to its stability.
Senior System Engineer at Atlas Security
In terms of Dell PowerScale (Isilon) specifically, we have seen a return on investment due to faster performance than our last few storage arrays, and the general usability is a lot better.
Storage & Data Protection Specialist at General Dynamics Land Systems
The second cluster of Dell PowerScale (Isilon) gives us flexibility for small things like code upgrades, all the way to scenarios where we have lost this data center or data, allowing us to check if data is still intact on the other side.
Senior System Engineer at a healthcare company with 10,001+ employees
The solution can comfortably be stretched from five to seven years without any failures, ensuring a long-lasting return.
Infrastructure Technical Specialist II at Clicks Group
We have seen return on investment compared to other OEMs, which took approximately three years after implementing IBM FlashSystem.
Technical Lead at Tomia
If you have the configuration well maintained and configured, you should have good efficiency and compression for the clients and for yourself.
System Engineer at a computer software company with 1,001-5,000 employees
 

Customer Service

Sentiment score
7.3
Dell PowerScale users generally find support satisfactory, noting responsiveness and knowledge, but highlight inconsistencies and areas for improvement.
Sentiment score
6.9
IBM FlashSystem's customer service is responsive, yet technical expertise and support vary by region, with contract complexities noted.
Sentiment score
7.3
NetApp FAS Series is praised for reliable, responsive support, though some seek faster resolutions and enhanced first-tier expertise.
Support online is definitely a ten out of ten.
Pre-Sale Engineer at Arab Operators
When we face issues, we raise a ticket through the valid portal, and they respond immediately and assign a local engineer to coordinate the support process.
Senior System Engineer at a financial services firm with 10,001+ employees
Dell provides support within four hours, and they always fulfill their promises.
Senior System Engineer at Atlas Security
Customers of alternatives like Dell and Hitachi enjoy more reliable and comprehensive support services directly from vendors rather than third-party subsidiaries.
Vice President Sales at BELOCAL LTD
I rate the technical support from IBM as a ten.
Infrastructure Technical Specialist II at Clicks Group
IBM customer support is responsible, efficient, and responsive, though it is expensive.
Manager, Technical Services, IBM Storage & Backup Solutions. at Thakral
Sometimes, the support was inadequate because the initial architecture was poorly defined.
Pre-Sales Director France, Belgium and Luxembourg at a tech vendor with 5,001-10,000 employees
We are also using it ourselves for the SAN and CIFS protocol.
System Engineer at a computer software company with 1,001-5,000 employees
They often provide basic solutions, such as suggesting a failover or a power cycle, which are not the sophisticated solutions we expect from a vendor.
Senior Cloud System Engineer at Atos Poland
 

Scalability Issues

Sentiment score
7.2
Dell PowerScale offers seamless scalability, supporting diverse storage types and accommodating significant workloads to meet future storage demands.
Sentiment score
7.3
IBM FlashSystem offers scalable storage solutions with dynamic upgrades and flexibility for medium to large enterprises despite some hardware limitations.
Sentiment score
7.3
NetApp FAS Series offers high scalability with Clustered Data ONTAP, supporting growth despite cost and complexity challenges.
We started on PowerScale with around about 300 terabytes and are now two and a half petabytes, still on the same file system.
Storage Architect at a educational organization with 10,001+ employees
That's really saved us in certain areas as we didn't have funding to expand Dell PowerScale (Isilon) until next year, which is why we utilized the cloud pools functionality to offload.
Senior Infrastructure Specialist at a healthcare company with 10,001+ employees
As an unstructured data storage solution, writing into it and accessing it from the other nodes is highly scalable with no issues.
Senior Technical Engineer at a tech vendor with 10,001+ employees
For larger enterprises, scalability is an issue as the price becomes prohibitive.
Vice President Sales at BELOCAL LTD
The problem arises when migrating data to a later IBM FlashSystem version due to issues with firmware compatibility.
Manager, Technical Services, IBM Storage & Backup Solutions. at Thakral
The scalability of IBM FlashSystem is exceptional, and I rate it as a nine.
Infrastructure Technical Specialist II at Clicks Group
We normally avoid current versions and use versions that have been running for at least two months in client usage before updating drivers.
DIRECTOR at Vellore Online Systems
NetApp FAS Series is scalable, and it is possible, but you need to pay.
System Engineer at a computer software company with 1,001-5,000 employees
The NetApp FAS Series is scalable and offers numerous solutions, but only if customers are willing to invest in the shelves.
Senior Cloud System Engineer at Atos Poland
 

Stability Issues

Sentiment score
8.1
Dell PowerScale is praised for stability, reliability, easy management, and high uptime, with infrequent, manageable hardware issues.
Sentiment score
7.6
IBM FlashSystem is praised for stability and resilience, with minor issues resolved quickly, earning high feedback for reliability.
Sentiment score
7.9
NetApp FAS Series is reliable and stable, with minor issues swiftly resolved, earning high stability ratings despite occasional challenges.
Since we have good protection levels, the data is secured and replicated across the disks.
Pre-Sale Engineer at Arab Operators
Even if a node goes down, other nodes can respond and provide data back to the user without issues.
Storage Platform Engineer at Expedia Group
I assess the stability and reliability of Dell PowerScale (Isilon) as perfect.
Storage & Data Protection Specialist at General Dynamics Land Systems
Customers have infrastructure that is 100% stable.
Manager, Technical Services, IBM Storage & Backup Solutions. at Thakral
The firmware and software engine have fewer bugs, which enhances operational efficiency.
Infrastructure Technical Specialist II at Clicks Group
When panic occurs on the node, it reboots itself, and we have experienced numerous hardware-related issues.
Senior Cloud System Engineer at Atos Poland
Most things are tailor-made, and we avoid downtimes even with primitive CLI commands.
DIRECTOR at Vellore Online Systems
 

Room For Improvement

Dell PowerScale (Isilon) users face integration, usability, and scaling challenges, with needs for improved support, security, and AI features.
IBM FlashSystem requires enhancements in scalability, integration, user interface, and support, with better deduplication, monitoring, and streamlined processes.
NetApp FAS users desire better performance, documentation, UI, cost efficiency, cloud integration, automation, support, and competitive pricing.
Hardware failures under warranty should be addressed within the promised timeline.
Senior Engineer at Continental Tire
I would want to see more AI features with Dell PowerScale (Isilon).
Storage & Data Protection Specialist at General Dynamics Land Systems
If I could improve one thing on Dell PowerScale (Isilon), it would be better object storage as it recently breached into S3, and that capability could be broadened.
Senior System Engineer at a healthcare company with 10,001+ employees
Despite marketing promises, these features do not function effectively and can impact performance.
Vice President Sales at BELOCAL LTD
There is room for improvement in the troubleshooting part, specifically related to IBM Spectrum for Insight.
Manager, Technical Services, IBM Storage & Backup Solutions. at Thakral
An additional function that could be helpful is reducing the time it takes to delete volumes, especially if they are compressed or deduplicated.
Storage Specialist at a computer software company with 1,001-5,000 employees
Storage companies should create encrypted storage solutions between the OS and storage to protect against ransomware attacks.
DIRECTOR at Vellore Online Systems
Nutanix leads the business in this approach, and I feel that NetApp is missing some aspects, such as CPU, GPU, and RAM, in its AI portfolio.
Pre-Sales Director France, Belgium and Luxembourg at a tech vendor with 5,001-10,000 employees
There is an opportunity there for NetApp with Cloud Volumes ONTAP.
Technological Consultant at a computer software company with 11-50 employees
 

Setup Cost

Dell PowerScale is costly but valued for its features, flexible licensing, scalability, and long-term cost efficiency.
IBM FlashSystem offers competitive pricing, but evaluating long-term needs and negotiating discounts is crucial to manage costs effectively.
NetApp FAS Series is costly but offers value with features like deduplication; planning and negotiation optimize ROI and pricing.
It's quite expensive for the amount of storage we have.
Senior Infrastructure Specialist at a healthcare company with 10,001+ employees
Cheaper nodes will cost less, while higher performance nodes will be pricier.
Storage Platform Engineer at Expedia Group
Costs align well with what it delivers, making it a fair price for a powerful tool that meets all our needs.
Tv Systems Technical Supervisor at a media company with 501-1,000 employees
To install or upgrade any software features, the cost is high, which makes it challenging for smaller companies who do not require advanced features like deduplication or compression typically needed by larger organizations.
Vice President Sales at BELOCAL LTD
The pricing is high; storage solutions are always expensive.
Freelancer at a logistics company with 10,001+ employees
The pricing of NetApp FAS Series is not cheap, but in comparison to other vendors, NetApp FAS Series is affordable.
System Engineer at a computer software company with 1,001-5,000 employees
 

Valuable Features

Dell PowerScale provides scalable, efficient storage with strong integration, data protection, and easy administration to enhance operational efficiency.
IBM FlashSystem delivers high performance, user-friendly management, and scalable efficiency with robust features like deduplication and virtualization.
NetApp FAS Series offers performance, flexibility, and reliability with robust deduplication, seamless integration, and efficient data management for diverse environments.
Dell PowerScale offers high scalability and stability as well, making it a valuable solution for enterprises.
Senior System Engineer at Atlas Security
In our AI initiatives, Dell PowerScale (Isilon) plays a significant role in data analysis, data fusion; principally, it is involved in data analysis, data extraction, and statistical analysis.
Senior Technologist at a university with 1,001-5,000 employees
Single files are limited to four terabytes in our configuration, however, the system can support up to 16 terabytes, so we can scale based on that too.
Systems Engineer at Unisity LLC
There is a significant amount of data reduction, achieving a ratio of one to three.
Storage Specialist at a computer software company with 1,001-5,000 employees
The most valuable features are performance and reliability.
Freelancer at a logistics company with 10,001+ employees
There is built-in compression, a data reduction feature, and artificial intelligence-driven insights that calculate warnings and errors to redirect to customers automatically.
Manager, Technical Services, IBM Storage & Backup Solutions. at Thakral
While NVMe disks are expensive and require three disks for parity calculations, hard drives in NetApp FAS Series are inexpensive, making it more cost-efficient per GB, even with RAID tech implementation.
Senior Cloud System Engineer at Atos Poland
Our IOPS are very high, reaching somewhere about 50k to 150k or 1.150k.
DIRECTOR at Vellore Online Systems
One important feature for customers is its ease of use and continuity, enabling seamless usage across on-premise and cloud environments.
Pre-Sales Director France, Belgium and Luxembourg at a tech vendor with 5,001-10,000 employees
 

Mindshare comparison

As of April 2026, in the NAS category, the mindshare of Dell PowerScale (Isilon) is 15.5%, down from 17.6% compared to the previous year. The mindshare of IBM FlashSystem is 7.2%, down from 13.6% compared to the previous year. The mindshare of NetApp FAS Series is 10.8%, down from 12.3% compared to the previous year. It is calculated based on PeerSpot user engagement data.
NAS Mindshare Distribution
ProductMindshare (%)
Dell PowerScale (Isilon)15.5%
NetApp FAS Series10.8%
IBM FlashSystem7.2%
Other66.5%
NAS
 

Featured Reviews

BE
Systems Engineer at Unisity LLC
Flexibility and reliability have supported seamless data growth
I cannot think of anything to improve about Dell PowerScale (Isilon). The hardest challenge we have is due to how we've bought things over time. The way that we moved to the PowerEdge platform for the newer systems creates a scale problem as I still buy the older style systems, which are more dense storage. They're different chassis, so the problem we run into in the data center is the depth of the actual equipment. The newer equipment, if we buy an FX910 or a 900, it's a lot shorter in scale than if I buy an 83,000, which is much bigger. This makes it more complicated for deployment.
OmarIsmail1 - PeerSpot reviewer
Infrastructure Technical Specialist II at Clicks Group
Offers high performance and dependable support for fast storage needs
The most valuable feature of IBM FlashSystem is its robust back code. When integrated properly into the environment and configured according to the guidelines, it provides a very solid infrastructure that does the job on demand. Additionally, IBM FlashSystem offers competitive pricing and reliable performance. The hardware is dependable, ensuring that it functions effectively when the setup is done correctly.
Srikanth Purushothaman - PeerSpot reviewer
DIRECTOR at Vellore Online Systems
Has supported long-term data protection and backup while requiring better part availability and pricing options
For monitoring purposes, we normally use flash access storage exclusively. We utilize a hybrid system because we need performance, combining NL-SAS for the volume and SAS flash to use as a fast cache system that provides more IOPS. We normally implement RAID 10, which we prefer over RAID 6's n plus 2 combinations. We utilize it for data redundancy, even with write intensity on. Regarding the unified storage architecture for NetApp FAS Series, we normally opt for exclusivity unless budget constraints exist. Our IOPS are very high, reaching somewhere about 50k to 150k or 1.150k. The high performance ensures minimal latency. An advantage we've seen with NetApp FAS Series is that snapshots provide very rapid backup and fast recovery. We basically use snapshots for data protection as first-level protection, with deduplication between the two storages serving as second-level protection.
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Top Industries

By visitors reading reviews
Manufacturing Company
10%
Computer Software Company
10%
Financial Services Firm
9%
Government
8%
Computer Software Company
10%
Financial Services Firm
10%
Manufacturing Company
9%
Comms Service Provider
7%
Manufacturing Company
15%
Computer Software Company
10%
Financial Services Firm
8%
Construction Company
5%
 

Company Size

By reviewers
Large Enterprise
Midsize Enterprise
Small Business
By reviewers
Company SizeCount
Small Business19
Midsize Enterprise20
Large Enterprise44
By reviewers
Company SizeCount
Small Business47
Midsize Enterprise21
Large Enterprise59
By reviewers
Company SizeCount
Small Business31
Midsize Enterprise38
Large Enterprise58
 

Questions from the Community

What do you like most about Dell EMC PowerScale (Isilon)?
The solution provides massive performance, scalability, efficiency, and ease of management.
What is your experience regarding pricing and costs for Dell EMC PowerScale (Isilon)?
As I mentioned before, we did not purchase Dell PowerScale (Isilon) directly. Since our organization is a government ...
What needs improvement with Dell EMC PowerScale (Isilon)?
I have experienced a RAM failure in some of the nodes of Dell PowerScale (Isilon), and that required hardware replace...
What is your experience regarding pricing and costs for IBM FlashSystem?
The pricing is high; storage solutions are always expensive. I do not know if the price needs to be reviewed, but it ...
What needs improvement with IBM FlashSystem?
As far as I know, IBM FlashSystem has already improved, but I do not see room for improvement. It is simple to use an...
Which SAN product would you choose: IBM FlashSystem (FS9500) vs PureFlash Array/X NVMe vs PureFlash Array/XL NVMe?
Have you considered a NetApp FAS Storage for your NAS needs? I am sure it fits very well.
What is your experience regarding pricing and costs for NetApp FAS Series?
I do not handle the pricing part of NetApp FAS Series since it is managed by the sales team.
 

Also Known As

PowerScale, Dell EMC Isilon
IBM Storwize
No data available
 

Overview

 

Sample Customers

OMRF, University of Utah, Translational Genetics Research Institute, Arcis, Geofizyka Torumn, Cyprus E&P Corporation, Colburn School, Columbia Sportswear, Harvard Medical School, University of Michigan, National Library of France,
Celero, Friedhelm Loh Group, Clarks, Mingkang Natregro Health Food Group, Sofia, Etisalat Fights Fraud, UF Health Shands Hospital, Generali, Elecon Engineering Company Limited, Ventiv , Technology, CPFL Energia, Royal Caribbean Cruises Ltd., SciQuest, Coca-Cola Bottling Co. Consolidated, Paddy Power, Kelsey-Seybold Clinic, Interconnect Services, Severstal IP-Only AB, PVU Group GmbH
Children's Hospital Central California, Plex Systems, PDF PNI Digital Media, Denver Broncos, PDF KSM Legal, Clayton Companies, Virginia Community College
Find out what your peers are saying about Dell Technologies, NetApp, CTERA and others in NAS. Updated: March 2026.
885,444 professionals have used our research since 2012.