As it is thin chair wheels sink in at take a "set " which can make it initially hard to roll the chair. I suspect this will lead to it breaking down (they all do) faster needing earlier replacement. It is a nice size. The thicker (and more expensive) ones were much bigger.
I use this mat over a vinyl floor. It needs to be much thicker to provide a smooth rolling surface. I have a chair with 5 casters on it and they create divots on the mat. I weigh 200 pounds; so that distibuted over 5 casters should not create divots in a supposedly solid pad.