get it, they are good fun to ride and I find them uber cool...
They are not as reliable as, say, a 2002 Yamaha Fazer 1000 with 50k miles (worth £1900) or a courier Divvy and they are also quite expensive to fix especially as OE parts are out of this world expensive (and BMW labour). Overall though they are not that bad. A couple of well known issues you have mentioned like fpc and final drives & gearbox gaskets affect abt 20% of the population of bikes by my roughstimate and thats it. Forum are for people to complain and vent off so one gets a biased view by reading us here...
The fact remains that the GS is the coolest thing on two wheels on the reliable half of the biking spectrum...
Of course you can also buy a KTM (in Greece - most popular ktm market per capita in the world - we say that KTM stands for Kathe Triti Mastora which translates like "every Tuesday to the garage for repairs)
Or a Ducati... speaking of which I have a 96 Monster (m900) in boxes in my mom's garage in Athens minus a few bits and bobs like half the mangled electrics.... Bike broke down after 3 years while riding in the rain - itself a rare thing.. No (greek) shop has managed to trace the issue ever since until I stopped trying. Its been rotting away since 2000 as I never had the guts to sell/bin it. Eventually I left it on the pavement for 2 weeks (iis 3 big boxes + frame and wheels) and no one took it in a country where you d lose your wallet in a second..., so happy to give it away if someone pays the shipping... Its no pile of rust, just about.. oh and nothing works...
So I ended up with BMW for style, I also fancy harleys, but talking about rubbish....
Unfortunately as I keep saying in forums, relaibility is inversely proportional to style...