I'm not sure I agree about the negative feelings towards BMW still being the case in the UK though; the 'BMW driver' thing was perhaps prevalent up until maybe 5 years ago, but more recently I think there's a lot of respect for the brand now.
With all the praise coming in for BMW recently, from owners and the motor press - even from Top Gear, who were in the past a bit anti-BMW, with their praise for e.g. the 1M and M5 and M135i - and the fact that they're clearly making the best-in-class cars for performance, fuel consumption and emissions, and obviously the drive; coupled with their very positive presence at e.g. the London Olympics this year, I think these days those thoughts are mostly gone?
As Jeremy Clarkson said a few years ago - the old cliche of a 'BMW driver' is perhaps now the new Audi driver; and the new driver/owner of a BMW is now often just someone who appreciates the drive, rather than just the badge. This has certainly been my experience both on the road and in conversation - generally speaking, of course! There will be exceptions to both.
I think the types of people interested in BMW now have changed - generally speaking - as the cars and the brand itself has changed. I hope others agree! Because such feelings aren't deserved now
And when people do still hold those prejudices, it's usually because they know nothing about cars, and have just picked it up from elsewhere; so as you said, what that minority thinks (wrongly) isn't of importance anyway
Just my opinion as another UK BMW enthusiast - sorry to hijack your thread