Olfa self-healing is the only mat I would ever buy. I also seldom use the mat's measuring lines but cut everything using two rulers--one for cutting with blade and another to slide up/down fabric securing my specific measurement before cutting. I changed to this way of cutting when I asked my fellow seasoned-quilters why my quilts were always 1/4+ off at one end. Their comment was that the lines on any mat after long usage will begin to spread. Sure enough--now my quilts are just about perfect bottom, top and middle.