I have an Olfa and it has not been worth the money. I never thought I was very stong and I know my blades need changing but have had to duck tape where it has cut through. And yes, I have tried to cut in different places. I am looking at an Alvin..self-healing, 3mm thick (supposed to be thicker than an olfa or Fiskars), and is used by graphics designers, framers, sewing, etc. So I assume since it is used by the "professional" people, it would be a stronger mat than the others mentined. The price is about the same. Anyone used one of these?