It's a bit too soft -- chair makes indentations in the mat and then isn't able to move easily out of the "pits" it has formed so it's sort of "frozen" in place until I give it a big push.
The chair casters still leave a dent in surface. If you move it they “heal” but not sure of long term life. Also doesn’t appear to have longer “ spikes” for thicker carpets.
It is a great mat if no one sits in the chair. With someone in the chair the casters make big dimples in the mat which makes it difficult to move the chair. The cleats on the backside are not deep enough to prevent the mat from sliding. I finally had to screw the mat to the floor.