I have high pile carpet and I'm not a small person....so the chair mat needed to be thick for both reasons. This one works well. Whatever denting I've put into it seems to disappear after an hour of not being used. The bigger size is useful too.
Picked this up at the local store they had plenty rolled up ready to go. It will dent up some if I sit too long in one place (I'm a heavyweight) but next morning it's smoothed out. Chair rolls nicely on it ove the carpet.