I bought the biggest Olfa mat this last Christmas and after a few weeks the mat started peeling off in strips. It came loose at the intersection of the cuts I made using the rotary cutter. I could peel the top layer off in strips. I contacted Olfa and was told, I still have the email, that it must be my fault for not cutting properly and Olfa mats were not guaranted and so not replaceable. But if I would mail the damaged mat to Olfa, she, the customer rep, would replace it this one time. I'll stick to Fiskars, I've never had a problem with their mats and they replace any product anytime.