Bought less than a year ago and the thin vinyl is already cracking wherever the wheels roll. I bought one of these from a competitor over five years ago and it lasted that long for the same price. Shop around!!!
If it is not on a "hard" or firm surface it will flex too much. If the carpet has any pile you get divots in the mat and the wheels sink in. It too thin for long term use on carpet.
I purchased this mat to replace another which had lasted for over 25 years until it began to crack and I could not roll my chair over it with ease. The new mat which was placed on LOW pile carpet does not serve its intended purpose at all! It is half as thick as my old mat and the grippers (teeth?) on the underside do not hold the mat in place at all. Each time that I use the chair the mat moves away from my desk and it (because of its thinness) makes it extremely difficult to roll the chair with any kind of ease. If you want a leg workout then this mat could prove useful but not for what it was intended i.e. easy motility while sitting at your desk.