Needed this for a new job that is home-based. It doesn't move much so that part is at least correct. But it does indent very easily. I am only 170 pounds and my chair is constantly making huge indents in the plastic while I am sitting on it. They almost completely go away when I move my chair out of the holes. But it is still really annoying.
Bought this mat with a new chair (which I love!) and found it to “dimple” under the chair wheels making it hard to roll. Thicker plastic would help it keep a flat shape.