I have been conducting a "torture test" if you will on the venerable Tenacious for the past month or so, putting it through anything and everything I can possibly think of. There is no science involved or anything of that nature. I am just going above and beyond to beat the hell out of my utility knife too see what it can withstand. Over the past month I have done a fair amount to it, from dropping off of a roof onto the asphalt, to just cutting things just for the sake of cutting them, like metal cans, etc. During this abuse, I will not maintenance the blade in any form or fashion, including sharpening. It has held up extremely well so far. I'll Update with pics and so on when I am done beating it to death, or if it finally gives in. Thus far, it has not really had any functionality issues, nor has it had any play develop. There isn't any rust formed either.