This carpet protector seemed to work for for about 6 months but then developed a tear which turned in a large hole making it useless. I'm going to contact Staples about a no charge replacement under warranty.
My old chair mat got so brittle with age that it broke apart and the chair wheels were getting stuck in the holes so this one is a nice change for me. It seems to be thick enough and keeps its position on the carpet without moving around. I wish it were a little bigger but I did not want to pay what the bigger ones cost. I like that it's clear because you can see the carpet color underneath and the mat isn't so noticeable. I've read reviews of cheap chair mats where the customers complain that they're so thin the chair dents deep into the mat and makes it hard to roll the chair around. I don't have that problem with this mat. It dents in slightly which isn't a problem.
A good serviceable mat for the money. Would have preferred a rectangular mat of the same dimensions without a lip but for the price I can live with it. Only downside is that previously purchased mats of the same kind have tended to crack and break apart after only about six months of use. These do not smell of polypropylene for a time after installation as do some competitors.
I bought this for my wife to use at her desk at home. It is just the perfect size--not too big and not too small. We have medium pile carpet and this chair mat seems to work great with it. It certainly will protect the carpet from wearing as the desk chair rolls around on it.