In the 6 months I've had the car, I had my first "encounter" 2 days ago on my way home from work in a town 30MPH zone.
A white 320D X-Drive M Sport with the full M Performance kit pulled up alongside me at the lights and beeped his horn so I knew he was there.
When the lights changed, I just let him go as it was just not worth wasting my petrol on. He was probably telling his mates down the pub how he'd beaten an M5