Just thought I'd chip in on (one of) my local dealers...
I've purchased the "X" there, and had it in for one (oil) service. The sales guys are good, in the sense that they aren't high pressure, and they're not complete morons. And yes, I did clue them in on X5/3World for their customers!
As for the service department, as I said, I've only had oil service, but they were quick, efficient, and knowledgeable. The one downside is that you can't get a loaner unless your vehicle will be in for more than three hours. I don't know how this compares to other dealers, but there it is...
Also discovered a problem with one of the local radio station conglomerates. My radio presets were behaving strangely, and I mentioned it to the service guys. Apparently, the radio stations (Adventure Radio Group) causes this strange behavior. Something to do with their RDS and the Business CD radio. You'll have one station preset, and when you push it, you'll get one of the other Adventure Radio stations. Apparently nothing they can do.