We are a technical services company and we work with many different solutions, including the Sophos Email Appliance. We currently have a couple of customers who use Sophos.
This solution is for the secure delivery of inbound email. There are various use cases including checking email against spam, DNS or configuration related issues, and spoofing-related security issues. It also checks URL in emails, as well as for malicious attachments. All of these things are checked before the email is delivered to the user.