I have a wool hooked rug under my desk and the desk chair would not roll very easily which was frustrating - who wants to get up off their chair to move it when you're busy on the computer? This mat is perfect! The chair rolls easily the grippers on the mat keep it in place ALWAYS (but hasn't damaged the rug at all!) it's clear so you can still see the rug design underneath the mat and it's heavy enough that the mat does not bunch up or crinkle. Also appears that it will last a long long time. :)
So far this mat is pretty good. We have only had it for a short while so have not had an adequate time to test for discoloration or breakage due to to getting worn out. So far it is a nice floor mat.