This is a great product that functions as promised. Be very careful when unrolling and placing this item. The teeth on the underside are SHARP and can take the flesh right off your hands and arms (also a natural lure for cats when rolled up). I would not advise letting kids help you with this. I put some bricks on it overnight after placing it on the rug. By morning it was perfectly flat and has stayed that way. This one is in my teenager's room and I plan to buy another one for my home office.
I have a corner desk and it could be about 6 inches wider on each side. Adequate for stationary work but I can't roll far without falling off the edge.