My warranty is 3/36. That is the warranty on all Roush Mustangs regardless of stage (RS, RS1, RS2,&RS3). I figured it would have the standard Ford warranty too but I was wrong.
Roush does offer a power train warranty for up to 3/36 from in service date if the phase 1 kit is instlled by an authorized shop. My car will hit the 3 yr mark in April I think. Of course this warranty cost an additional $400 or so. I have already figured that into my price.
I was hoping someone on this forum was running the 626R package to give some input. I've read several folks running the 650R kit, but none for the 626R.
Does Roush put some sort of tune in all of their cars? Stage 1 is only cosmetic and Stage 2 (Roush cars, not supercharger phases) is suspension based from what I recall, that shouldn't have any effect on your 5/60 powertrain warranty from Ford. If your motor fails, it's on Ford to prove the failure is due to a cosmetic/suspension related mod from Roush. You never just completely "lose" a warranty, unless it expires obviously.