You are doing a range of tasks pretty much what I do, cardboard is very abrasive on knives most users know that. I've built and tested thousands of knives for a maker and I assure you I can feel flex in blades with thin stock even up to .16 So far this 2.8" inkosi isn't too bad, it gives a little on 3 layer cardboard but has good control and is holding a good edge, I'd bet the 3.6" blades will flex a bit more, simple leverage. Thanks for the input.I can honestly say I've never felt one of my CRKs flex. And my use tends to be a little bit harder than cardboard.