There's a select group of repair technicians, well known, mentioned often on this forum, and they do great jobs, but repairing a camera is not rocket science. I've had Zeiss cameras repaired by people not named Henry, and they've come out fine without busting the bank or waiting five years. I've used DAG and Sherry (Sherry often) and they've done great jobs, and they charge what their reputation demands, but I've had other people repair Leica cameras (and lenses) for less, and they did good jobs too.
One item to consider is that some of these repair techs have access to spare parts other do not. I'm fairly sure Sherry Krauter for example bought up all the spares for M5 and Leicaflex from Leica USA (or am I just imagining that?). Not every camera though needs replacement parts. Usually meter stuff.
Sometimes you hear on these forums that cameras are mystical things that only a few special people can repair. That has not been my experience.
Heck, a lot of forum members do their own repairs.
Then also remember Cameraquest (you know, the guy who owns this forum), well, he repairs cameras too.
So I echo the comments above about back log and general reputations.