being a heavier guy..have noticed dents in the chair mat after sitting for a while in the office chair. Has lots of fingers underneath so the mat doesnt move. Plenty of room to move around in the chair also. Maybe a thicker chair mat would help not to get those dents.
I needed 2 mats for my scrapbook room. Easy to clean small paper clipping from. My chairs roll with easy and yet they aren't too large for my cropping space.