Although it's easier for my chair to roll across the carpet this mat could be thicker because the chair wheels make dents in it and get stuck. The chair mat also shifts and doesn't stay in place.
This mat like another larger one that I purchased at the same time does not have the gripping power to stay in place on my medium-pile carpet. The mat moves on the carpet constantly and has to be repositioned at least once a day. Very annoying.
I ordered a chair mat and when it was delivered it was very dirty and had several big bumps in it. It was not flat and took two days with books piled on it to lay flat again. I was expecting to be able to use it right away like the last time I ordered one.
If your chair stays in one position for a while you need an extra 'shove' to get the wheels moving again. I would still probably recommend it with that caveat in mind