I've had my 1150GS from new in November 2003. It has the servo brakes which have not given any trouble in 50,000 miles. I'm certain that they will fail at some time and that is a concern. I hope it's not when some clown pulls out of a side road in front of me or when I'm braking for the hairpin at Knockhill!
I've also had 1200GS demonstrators as loan bikes several times over the years whilst mine has been in for a major service. I was never happy with the front end feel from the earlier 1200's and it is only the latest revision for model year 2009 that feels good enough to maybe tempt me.
However the 1150 does nearly everything I need of it from commuting including filtering to track days (where I need more accelertation) and off roading so why spend another £10,000 less around £3,000 for a ratty part-ex?
Then of course there is the proliferation of plastic on the 12's. It will probably fade horribly over the years and be very expensive to replace.