My office chair left dents in the mat without anyone even sitting in the chair! This is definitely not worth the money. The dents don't pop back out they are there for good. When I sat it it was hard to move because the chair rollers were in the dents.
When used with a plush carpet w/one inch pad it will creep as chair rolls on it. Needs to be more heavy duty with longer pins to hold it in place on the carpet.
The adhesive sticker that is on the mat is not able to be removed easily. I put that section under the desk so I didn't have to spend time trying to remove it in its entirety.
Since I spend several hours every day on the computer I appreciate the ease that I can now move around in my office chair thanks to the great floor mat!