Overall, my service experience has been pretty good.
My first encounter with the service departments was bringing in my car after I had discovered it had been vandalized. I looked at the time, and realized it was noon on a Sat- which is when most service departments close. I asked if I could bring it in, and they waited for me.
I've been a customer now for almost a year, and have been very happy with the customer service and treatment. Its what I would expect from BMW.