I only have experience with the sales staff and a little of the repair, bought my M3 from them and a friend got an Audi a few years later. They fixed the minor things on it and seemed friendly and knowledgeable. I am not sure if they are still there but Brian was one of the lead repair people for the BMW's. Talking to him he knew his stuff, I would have had my repairs their but I moved out to South Riding.
I don't know if this says much but the M3 and the Audi were in great shape and we never had major issues that were not expected. So at least the buyer knows what to look for, where my next used car had a lot of issues, not from them. I would have gone back to Fairfax Motors but they did not have what I needed at the time.
Let us know how they are.
Found a link, this guy http://www.fairfaxmotors.com/BMW_Service.html