The flat pile Carpet Chair Mat was "okay". It could have been little thicker since the chair rolls and the mat bends as it rolls. The carpet is Berber so it should have worked better since the carpet is flat.
This is a sturdy mat and I am very happy with it. My old one was thin and got low places in it and then cracked from those indentations. I guess you get what you pay for.
I needed to replace a chair mat that had cracked. I purchased this as a replacement. It fits perfectly between the U shaped space between my desk. My only suggestion is to make these more durable. They don't last more than a few years even though they are not supposed to crack. This one shows the indentation of my office chair and I suspect that it won't last any longer than previous chair mats.