It is just okay I can move my chair back and forth easier but I wish they would make one that is a little stiffer so that my chair rollers would not make sinks enough that it I hard to move the chair while sitting in it. If I were much heavier I could see that it might ;sink' in but I weigh 137 lbs and I would like to have one that would stay flat.....or at least flatter!!
This is an inexpensive chair mat and that is exactly what you get. Mine got a couple divots in it just from the chair but it works and should last a few years.
The mat works well on my Berber style carpeted floor. Casters roll well without the risk of damage which is the main reason for getting it. The material is thin and soft enough that it still feels carpeted when standing on it. That also means that 2” casters on my chair will sink a little but after two weeks I don’t see marks left in the carpet. My only critique is that the top surface should be more textured.