I am happy with the chair mat but I wish that instead of having the spiky parts underneath that it would be just smooth. I have a larger smooth one under the other desk I have and it lasts longer than the ones with the spikes underneath. But since I could only get the smaller one that I needed I took this one and it is working well right now but in a couple of years time when it "dries out" more then it tends to start cracking.
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.