This is a near duplicate to one I purchased 6 years ago and which began cracking. It cracked where my front chair roller resided most of the time when I worked at my desk. No I'm not heavy - 170 lbs.
the mat is probably fine for berber or short-hair carpet. I had it for thick carpet and it is not working well. It keeps moving and I need to adjust it daily
Only after two weeks of use the mat has developed these depressions and the chair gets stuck and is difficult to move. I am using the mat in my small home office and the chair isn't very heavy either...... its a task chair. The mat is very thin and the quality if inferior quality. Wish I could return it.
The material is too soft and the chair wheels make indentation ruts that are hard to move out of...I'd buy the Polycarbonate version but it's almost three times as much...