A buddy also has a 2017 RS. His head gasket replacement ended up being a nighmare scenario that a few folks had. His local dealership is really small and frankly Ford hasn't had any high-strung motors in their bread and butter cars for decades so techs can be sloppy overall, especially when they work on F150's, Escapes and Transits most of the time.It's a 2017 so it's going on 4 years. We have had zero issues.
There was a recall on the engine as some of them had a NON RS focus head gasket installed on them. That was a big goof but once Ford was aware of this, they notified all owners and we worked with our local dealer and got it swapped out. We had no issues with the incorrect part and it's been 3 years since the correct one was put on with no problems.
Long story short, it runs great now and is one hell of a motor.... No f-ing clue why this has just popped into my mind to ask him to borrow the car for a week or so to get a feel for the transmission and engine pairing..... Duhhhhhhh!