This is my second chairmat. I wore out my first one. The size is just what I wanted for my use and this one is perfect for a low pile carpet or rug. The wheels on my desk chair move easily over the mat.
Never had a chair mat from Staples that immediately sunk under the weight of chair and so could not move chair without effort. Go back to what you had before. These are too too soft and don't hold the weight of a person and a chair.