Here in VA we are using Netop. The version of the program we have been using is very buggy and their customer supports sucks. Their response is always "Update to the new version". A few of the problems we have with it are... Teachers complain constantly about clients not showing up or completely dropping off the teacher app at completly random times. A reinstall of the client is the only fix. It is slow and clunky when you get more then 30 computers going and has a tendency to lock up when you try to do things too quickly... Even with a fast computer.
A few of the pros, It has just about every feature you would ever need, It has an intutiave interface and it has a pretty easy learning curve for end users.
We use it in about 30-40 labs consisting of 30 computers each. I believe we paid in the area of $4000-$15000 per site for it so it is defiantly not cheap.. Hope this helps..