This mat is on a medium pile carpet. It immediately developed "dents" under the chair wheels. I have had it for only about one week so I do not know if it will develop any other weaknesses.
Arrived quickly and not rolled up (a problem found from buying through other sources). However after only using for 1 week depressions are already forming in the mat that limits the movement of the wheels on my chair. I’m a small person (about 115 lbs.) so weight is not the issue. My carpet is a low pile berber so according to specifications on website it should be the appropriate mat.
Thought for the few hours I sat in my chair this mat would work. My desk is on low pile carpet but the mat still gets grooves making it hard to roll the chair. Will use it till it's not use able then get the correct one for the carpet!
I don't know about anybody else but when I order something from a store I expect it to be at the very least clean. This mat was delivered to our house and it was disgustingly filthy. It had foot prints all over it and was dirty. It looked like it had been used and then sent to us. We were not happy and will think twice before we order from your company again.