I have had issues with cheaper mats and my chair wheels digging pits into them specifically bought this to avoid that and I'm ready to throw it in the trash after using from New Years to mid-April. It gets a lot of use but I weigh 185lbs would think that it could handle an average-ish weight but nope.
Nothing like trying to scoot around on your desk chair on carpet. NOT. Using the heavy plastic desk mat that anchors into your carpet without harming it saves the day. I can scoot from in front of my screen to the filing cabinet to the supply drawers with ease.
Good chair mat works with worn carpet my carpet is almost to the bare floor and it sticks very well. I wish it could be a little larger by 2 inches all around but OK so far.