I put in 2 yrs and 40,000kms on a 2007 F800s and loved every minute of it. The rear bearing did seize on me (just after the bike clocked over 45K) and it was expensive to fix as this was before the recall, so Budd's just blamed my 'non-dealer maintenance' and asked me to pay for the repair.
Despite the bearing issue I would buy one again if I were to go back to street riding. The bike was otherwise bullet-proof, super comfy on long treks required to get to any decent twisties and amazing on gas (as an added bonus needing only REGULAR) and a willing performer in the bends. Suspension is severely lacking though (for a sport-bike anyway) so I would consider that in your decision.
It is a machine with very niche appeal but if ticks the right boxes for you it will be a blast.
I've heard stories of guys heading back to their dealers with receipts and getting compensated from BMW for past repairs. You have nothing to lose by trying.
Pretty accurate sum up of the bike overall. It really is a blast to ride.