Needed it as to save what is left of my carpet. Which isn't much it helped stop getting those dents in the carpet from the wheels on the computer chair. Works like a charm!
I'm using on a medium pile carpet. Yes it dents and shifts a bit but they all do on medium carpet. I don't mind moving the mat back every few days. The material is a softer vinyl than my old one so I expect it won't break as readily. Dents are OK breaks are not. I wanted something inexpensive for a year or so until I move and this one will do OK.