I've had my MS with the cover for around 18 months - and haven't had any issues with it. If you put something extremely heavy that only sits on the cover - then you might have a problem. I also have the Tesla floor mat over the cover, and haven't worried about putting anything into the trunk area. Several months ago, I used my MS to move a lot of boxes (some heavy) when I was moving out of my house - and didn't have any problems (I didn't even worry about it at the time).