I'm in London, UK, and have heard the BMW thing as well. But I do not find it to be true. Rather, I have to say BMW drivers tend to be a little better than other drivers. The ones I find bad are those driving small cars as they tend to be either overly careful (light's red, 'hun, get a fricking move on instead of staring at me in your rear view mirror) or dumb (the road's about to narrow so either stay behind me or stick it into second gear and accelerate hard, coz your 4th gear acceleration aint gonna get you infront of me in time for the narrowing of the lane).

London cabbies are great, give plenty of space, always aware of what's around them. Thumbs up/ Buses are also real good. A couple of times I've come across the move-outta-the-way-cowboy-i'min-a-hurry bus driver, but hardly worth mentioning.

Drivers of more expensive cars are a touch more careful, I guess they have more to lose financially if they're involved in an accident and also they dont wanna damage their fine automobiles.

This reminds me, I had a tiny scrape witha person in a small car (see paragraph one).