I can only go off what Twinfan is currently going through, have a look at his previous threads, his 749 chucked him off without any warning, and it looks like the braking system was to blame currently (not confirmed yet). And he purchased his bike from Ducati Manchester also.
I cannot comment on their servicing if I am honest. I too know of a few horror stories, but you could probably say the same for any dealer in all honesty.
I live approximately 10 minutes away from Ducati Manchester and pass the place twice a day, although I have never had any of the Ducati's I have owned/currently own serviced there if that's anything to go on