The mice are pretty and easy to hold and use. That's where my positivity ends. The first one we tried was not reading movement correctly - it had huge lag and delays in reacting to movement. The second one we tried was mostly good. The back button got stuck but mostly worked well. A couple of days after starting to use it the computer it was on would start hanging or not responding. Unplugging the mouse completely resolved the problem both times it occurred. That machine had never had a significant performance problem before that moment.