I just tried these blades and noticed skipping and a bit of shredding. I will flip it over and see what happens, or pitch it and try a new one. Here is my dilemma...why in the heck did I go through 5 Olfa blades last year???? I use a new Olfa mat or my new 4x8 cutting table mat. It seems that I can only get one decent size project out of those blades, but I know it must be something I am doing.. :(