OK, sure I have a bias but am amazed no one else on THIS forum went here. Other posts here list these options too so we would reco PBW, rinse, Star San (or Saniclean). Many of the items here do not have chelators so might be great in your laundry but will not address mineral soiling issues, such as the beerstone you mention.
PBW has several chelators chosen specifically for mineral soils from brewing and Star San or Saniclean will leave your pot in an acid state, allowing it to naturally 'heal' its passivation and never corroding. Actually, stainless, by definition, cannot corrode, but steal can. Stainless steel can loose its 'stainless'-ness which is why it corrodes. Choosing an acid sanitizer is the easiest way for a homebrewer to help his Stainless stay Stainless without using the nitric/phos acid routines the pros use on their sizable set-ups.