Here are my experiences relative to your question.
I bought a new 2007 GSA in 2008, and didn't really start riding it much until 2009. (It replaced a 93' GS for me.)
To this point I've put about 88K miles on it. I've not babied it, but I've not really abused it either. It has seen several thousand miles of off-road riding. I feel that I've basically used it for the purposes it was intended.
I know I'm probably just jinxing the livin' shit out of myself here ..................... BUT, I'VE NOT HAD ONE MOMENT OF TROUBLE OUT OF THE BIKE. Seriously, not one thing. It's been only consumables and routine service. I did have the OEM battery fail within the first year, but I sorta' consider that to be a consumable.
I do the routine service myself. Since I ride 20-25K miles a season, I try to take it in to the dealer once a season to have them just check it over with a fine tooth comb. It's probably a false sense of security on my part, but I like having a guy that does nothing but service BMWs five days a week give it a good going over. Plus, EVERY time I've taken it in for the yearly check up, there was some sort of factory recall warranty work (ignition sensor ring, brake line, electrical component, etc.) that needed addressing, that was always done free of charge.
My experience couldn't have been more positive. I really have enjoyed that big pig. I know it's going to leave me walking one of these days .............. but I sure as hell don't sit around and worry about it.
(All the miles I put on my old airhead were trouble free also.) The GSA WAS NOT my first choice of bike. I think the 990/950 KTM would be a better tool for the type of riding I do. But, I'm a big tall guy and the 1200 was way more comfortable for me. Ergonomics is really the main reason why I ended up on the GSA. In retrospect I'm glad that I made the choices that I did.
One thing you'll learn about BMer riders is that we have our fair share of whiners and complainers. My guess is that most of those have unrealistic expectations, or they just like to hear themselves bitch. My professional diagnosis is that they just don't get enough "throttle therapy".
No complaints from me though.
Good Luck, and hope this New Year has you bonding with a good bike!
Pm me if you have any specific questions.