I first bought one because of work and finding house addresses in areas of towns I was not familiar with. There is nothing like a tailgater beeping to prompt a stall lol. £140 sounds expensive but when you take in the environmental disposal on top of the more complex changing procedure (with my first there was mention of running the engine for so long at certain revs, I think) and labour charges it can soon get there
My own mechanic wouldn't do it as he didn't have the right pump, so I had to use the Audi dealer. I was surprised how the general quality of care at the main dealer was so inferior to my one man garage service.
Yes, although I usually go to the main dealer I have had one issue too, with my last car, one one service when they jacked it up wrong and bent a part of the chassis. They did sort it quickly though and it was fairly old at that point. I have had poor service from other than the main dealers in the past and, with work, I needed good service. I still go there. Driving a hybrid meant that many lesser dealers would not be experienced enough, at least when I first got one.