Marc did an incredible job fixing my 2010 M6! I had a tricky engine issue that the dealer couldn't fix - loss of compression in one cylinder. The dealer technicians said they thought it was a piston ring failure or scored cylinder wall, claimed it was un-fixable and said I needed a new engine, which would have cost more than the car is worth. So I asked some of the independent BMW shop master techs who they would recommend to take a look at it, and Marc was recommended as the right guy to go to. Good thing I did. Called Marc, described the problem, he said "sounds like a broken valve spring, I've already fixed 5 of those on that engine". I towed it there the next day and sure enough he was right. Had it fixed a week later for a very reasonable price. I'll never go anywhere else.