When I bought my cutting table at Joann's, I also bought the white cutting mat to go with it. Not a good idea. I couldn't figure out why my rotary blades were so dull, even the new ones that I had just bought. Then I figured it out, its not a self healing mat, if I cut something on a spot that hadn't been used, it cut fine, just not where I'd previously cut. Make sure its self healing and yes, they are expensive