I am happy to see this subject again. I purchased ten packs on-line. All had the same lot number. I opened a package put one in my Olfa cutter and gave the other one to my sister. I absolutely love mine but she can't get hers to cut at all. The only difference is I cut right handed and she is left. Could this make a difference? I see where most of the board members love them but there are a few that have the same opinion my sister has.