It is good for being over carpet but when I sit in my chair it sinks into the plastic leaving prints. I only am 190 lbs. a male. So. It’s not smooth. Those marks stay there. It’s like to memory foam like. Lol
This mat protects the carpet and makes it easier to roll when seated. After sitting for a while it dimples under the castors and would be better if it were stiffer. That being said it is significantly better than nothing but carpet.