I guess I'm on my high horse here because I made comments on another post about tension. But I don't care what brand of blade, spiral or flat, it should be set at maximum tension. If it breaks on setting tension, change brands. I'm like Kevin. I don't do a ping test for high C, D or E. I can feel it when applying the tension lever. I can hear it just turning the saw on. I'm generally a bottom feeder and in doing fretwork, that upper blade clamp is changed a myriad of times. Do you think that in stretching that blade to the upper clamp, you are doing it the same every time? Heck no! Every saw blade needs to be taunt to work at maximum efficiency. Do you think I would want my table saw, chop saw or sawzall blades to be flimsy, so why should a scroll saw blade be. OK, said enough.