In terms of performance, scalability, and other factors, I would rate them around eight out of ten. I've encountered a few issues during deployments based on customer experiences. My first deployment was with the QFX5100-48S for a data center customer. I implemented layer-2 connectivity on them. Overall, I would say they're good for small-scale and medium scale so it seems these problems can persist for some time. However, the QFX series is still generally considered a good product and offers more flexibility than other options. It's very scalable. I haven't heard any customer complaints about scalability. In my experience, even the QFX5110 series extends for many years without needing upgrades. This scalability solves the challenge of needing to upgrade due to unknown internal problems, even when the release is stable.
