I dont leave the car with the Dealer... when I first got there he asked me if I put the V8 into an A4... after a rather long silence I realized this guy is an idiot, he had never seen an RS6... So I actively took part in the scan. I don't leave it there ever, all work thats been done I did either myself or I take the day off and take a camping chair, food and water & sit and watch. Sounds bad, but like you say... the level of service is rather rubbish. They have a handfull of guys that know what they doing... and then the rest are just good at turning a spanner... and not much else.
I bought it from a guy that was given a really limited amount of time to leave, and a lot of stuff to sell. the car started online a lot higher... but he only started advertising it 3 days before his flight (understandable as he was here for 11 years had alot of stuff. the RS6 was a toy. he had 2 Landrovers, 2 small cars, and 2 bikes). I went to visit him with cash. he had little option. we made a deal.