From PH today:
"I posted back in April on this subject. My car (M3 Saloon), had been broken into by smashing the driverís window and all they had done was access the diagnostic port.
I was aware of the issue with BMWs so as a deterrent I bought a disklok. This morning I woke up to find my car gone and the disklok at the side of the road looking like it had been opened with a can opener!
I guess I am lucky as 4 hours later it was recovered by the police. The Met police are aware of the problem and are seeing a lot of cars stolen.
Despite what BMW say the Met tell me this is not an issue with other manufacturers. If you are considering buying a BMW I would recommend you think again unless you have very secure overnight parking. BMW don't care about this they fobbed me off back in April and they will just do the same again.
Fortunately my car was recovered so quickly it will not even go down as a claim (so I am told by my insurer). Anyway, be warned. As for me that's it the car is going at the earliest opportunity so if anyone fancies a 58 reg BMW M3 with 25k miles you can have it (at the right price of course! ;-)"
Never argue with an idiot on the internet. He will drag you down to his level and beat you with experience.