Post #2 is spot on. The problem with DAG is that his service is a black hole. Years ago I sent him a camera, and after 12 months with no word, I just told him to send it back. I've sent Sherry a lot of work in the past -- R lenses, various Leicaflex , and M5s, and always received good and timely service, albeit at a cost. After a gap of several years, I recently sent her some new work, and apparently she is busier now, because the wait is longer (or I'm in her doghouse). YY is fast but I've had one issue with the camera I sent him. He did, however, fix a blacked out viewfinder of an M3 owned by my sister, salvaging the camera.
The availability of timely, competent repairs is becoming a factor in my acquisitions.