Getting another "one" -- does this mean another BMW or just another e60?? With the new technology being adopted by auto manufacturers worldwide, you can expect that every dealer's service department will increasingly encounter issues that it has not been trained for or otherwise does not have the expertise to fix and therefore cannot resolve all problems quickly. It would be helpful if these dealers just admitted up front that they have no clue as to how to fix your particular problem, instead of raising your expectations only to later frustrate you.

My experience with BMW dealers has been essentially the same as yours -- they overcommit and the underperform, with inconsistent loaner policies from dealer to dealer and the SAs don't seem to know enough about the cars to give you any real feedback as to what needs to be fixed (i.e., they rely heavily on the techs to troubleshoot, and if unsuccessful, you end up having to bring the car in again). The biggest problem has been with the software on the e60 (all software upgrades seem to take 4-5 days, instead of 4-5 hours).

I also have a Lexus, which has been recalled once. Although the service experience was superior to BMW, I still had to take the car in for service (in the best circumstance, a car is so well designed and tested that you never have to take it in); the Lexus dealer undercommitted and overperformed (told me it would take days to fix, but actually fixed it in one day), so I left happy. However, as with BMW, the SA had no clue as to what the problem was, but the technician actually fixed it.

It will be interesting to see how Lexus deals with problems on the upcoming RX400h. Although I expect the hybrid electrical system to have been well designed and tested, the inevitable problems in the field will have to be solved by the same technicians who fix the petrol engines....