I will let you know my opinion when Olfa emails me back.. I have only used Olfa cutters. Last week I decided to change the blade on the 60mm quick change, and it flew out of my hand. I had all the pieces, but couldn't get it back together. I took it into the LQS, and I compared it to their quick change, and theirs didn't have the washer, and it went back together easy. I think the bolt broke off the plastic piece. Olfa guarantees their products, so I want to see what they think.