Put this down under an office chair (with casters) to protect an old pine floor. The mat moves around a little but not so much that the chair rolls off. I'm not sure if the lip adds any value; maybe it'd protect the floor from hard or dirty shoes? Seems like decent construction I'm not worried about it cracking or anything. This is about the smallest size I'd be willing to go. Would definitely buy again.
Not the thickest for carpet with any depth it will quickly develop low spots where your wheels sit. But price point was better than any and for light to moderate use on low pile carpets it does the trick.