I'm disappointed with how the chair sinks into the plastic. I specifically bought this as it was rated for plush (high pile) carpet. The plastic is flimsy and not as thick as described. As a result there are permanent grooves in the chair mat which makes rolling the chair difficult.
It is good on plush carpet. I had a thinner mat previously and it cracked badly. So far this mat gives no indication that it ever will. I'm pleased with it.