Just too thin. Hard to roll on wheel sink way in. My old one was a little thicker enough to support the wheels fine but it cracked after years of use. Bought that one at Staples also.
The price was great but I wish it were thicker like my old one. My old one lasted for 10 years. I do not see this one lasting more than a year or two if I am lucky. It is too soft too so I am not sure if it is just the thickness or the rigidness that would make it last longer.