The heat worries me on brakes. Cycling cold-hot-warm-hot-cold tends to undo fasteners. The torques on brake disk fasteners are designed to mitigate this within other design constraints. Basically they over torque over designed bolts on the basis that a big lump is harder to turn and still has more clamping force when loose. The safety factors are large but I really don't know how large. If you change the materials you should change the torques. No idea what to, a clever chap in Germany used to tell me those and would alway deny there was any add on safety factor!
Don't forget there are different grades of stainless and remember stainless into other materials needs lube which in turn effect the torques. For say bodywork it really doesn't matter, for other things it's a harder decision.
I'll use A2 stainless on anything except brakes to be honest. Other grades and Titanium are so expensive you could just bin the normal steel once a year and still be in profit when the engine goes pop
Andy
