I have used them in the past. While they are o.k., they don't last quite as long as the expensive ones from Olfa., at least to me. I did just check my supply and I have two packages of 10 blade's each from Olfa and Cutters Quilt. It may be a while before I'm ordering more. It depends on how much you rotary cut and the fabric you use. Give one pack a try, you may like them, or they may get you through when your others run out.