The mat buckles on carpet and makes it hard for the chair to roll on it. Has to stick an unsightly piece of cardboard under it to allow chair to roll better.
I would have to say the only thing with the chair mats is unrolling them. They are so tough to unroll. Other than that they are perfect! I am so glad they have the different wood tons now.
The Staples carpet chair mat crystal clear 45x53 is the chair mat I buy for all our employees. The mat lasts a few years before it starts to chip in places from wear and tear. It's inexpensive so it isn't a big deal to replace every few years.