stainless is no cure for rusty flange bolts.
when the stainless is heat cycled that far, it will gall when you try to unscrew it, then you have to torch or zip off the bolts. cutting stainless is not fun.

the real fix for this problem is to havea muffler shop add a braided steel flexpipe after the ball conneciton. toyota never did this with the trucks, so guess where all the engine movement is absorbed in the exhasut system? the ball joint.