When I was shopping for a BMW I read about the rear bearing failures over on AdvRider on the F800GT. Too bad, the rear drive belt is sort of cool. That and other issues turned me off to that model. The boxer in all generations are not perfect, have some serious potential issues, but pretty well regarded.
You are likely right that if service is needed on a road trip my chances of finding a Japanese brand dealer or tech are greater. I don't know if thinking about 'what if' I need a repair when on a trip is the best way to plan? Between a BMW and the big 4 anyway.
I don't want to hijack this thread. Sorry. Back to regular programming.