I replaced a 35 year old mat that was stiff and brittle and cracked. This new mat is supposedly designed for medium pile carpeting but my chair wheels sink in so bad I have a hard time pushing away from my desk. I'm 5' 11" 180 lbs. I certainly shouldn't be exceeding any weight limits on this mat. If my old mat didn't have cracks and holes I would send this one back.
This chair mat is thin...very thin. I have it sitting on a thin carpet. Being so thin (and very soft) the chair wheels make dents in the mat. Considering what it is it wasn't cheap. For a couple dollars more I could have purchased a thicker sturdier mat. I would definitely not buy it again. In fairness if placed on a hard floor it would probably be acceptable.
I like the size but it's seemed to be softer I can see my roller indentations and I don't weigh much. I just hope it last my last one bought at Staples lasted me a long time until it cracked. When I roll my chair it seems to be a little harder due to the softer product it's made of.