Chair mat is too pliable so your chair sinks into it and then is hard to roll if you're sitting in it. The mat is designed for carpet but it just a tad better than having a chair on the carpet with no mat. Spend the extra money and buy a better quality mat like I wish I'd done. I'd return it but already took off the tags etc.
The mat indents where the chair wheels meet the chair mat making it difficult to roll. Additionally the mat seems to scoot a little on my carpet and hence the mat buckles where it meets my desk. I wish I had bought a more expensive mat.