The mat is working out very well. i wanted something smaller for on my carpet but now realize that I should have gone a little wider to cover the entire area behind my desk. Also I thought I had a medium pile carpet vs. deep pile but the mat moves and slides on the carpet as I roll my chair. So next time I will buy a mat for deep pile. Right now I just anchored the front corners under my desk to keep it in place.
The plastic is quite soft so when I sit in the chair on the mat it creates an indentation. This helps to keep the chair in place but when I try to move the chair I have to push harder to get out of the depression it created. If my movement isn't significant the chair rolls back into the depression. I think the plastic needs to be firmer to get a higher rating than 2. Other than that it is a nice plastic mat!