We decided not to use it. It was so flimsy that if you set on it on one side the other side would life up. It wouldn't lay down. My mother tripped on it twice and we got rid of it.
Because of limited space I chose a small size chair mat and so far I'm very pleased with it. It lays flat and I like the way the lip fits under my computer desk.
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.