So far this mat is doing great. It doesn't slip and my chair rolls smoothly. I do wish the piece that goes under the desk was a little larger since I do roll off the mat on the front end however that is only a very minor gripe. The last mat I had cracked very early on (it was purchased in-store folded down the middle). First it cracked several times down the middle seam then over the next year developed micro-cracks all over. So far this new mat is holding up well without a single crack (about 2 months in)!
I chose one of the less expensive floor mats as a beginning point. This one would be fine on low pile carpet with very thin or no padding. I am not heavy and the chair wheels sink into the mat and into the padded carpeting. The good part is the mat is sturdy enough it has not cracked in the 2 1/2 months of ownership.