We have used Netgear UTM's for the past 3 years with decent success.
Customers love the products but they lack in 2 critical area's:
1. Lack of a virtual appliance. In physical network environments they are great, or in single company virtual environments they are too but when your looking at shared VM usage you lose a lot.
2. Their firmware seems to have outgrown the hardware. The new Application Monitoring is great, but it also kills performance and I'm seeing too many flaky things to make me continue to feel comfortable.
I saw Cyberroam on the web, never heard of them but looks to do the same as Netgear and also they have a virtual version of their UTM which is great for a shared VMware environment.
Thanks