I was surprised to receive my floor mat unpackaged with just a shipping label attached. Then I realized a "curl" would be a minor hassle. I used to sit and work at the computer I would find I had rolled back about a foot. I don't know the science behind this mat but my chair doesn't roll back with this mat. It's invisible on my oriental rug and doesn't shift around (there are nubs that are for that). Little gripper nubs that grab the carpet.
I am disappointed that my chair with 5 double rollers distorted the mat in two weeks such that my chair would no longer roll to where I wanted it or to let me up. I didn't even have that problem on the carpet. The description here says for "Flat Pile Carpet". I've seen flatter carpet but mine is certainly not plush. And I'm not big - about 175 pounds or about 35 pounds per wheel. Not very useful for me.