Driven F30 and now driving F10, i would say I am bias towards the driving and handling of the Beemer.
My colleague is driving the new A4 2.0T now, quite ok in term of handling and power, but the external look is not even comparable to the competitors, interior wise is way better than Beemer but not as posh as Benz.
Another friend is driving a Benz C200, is good for luxury and comfort, power wise need to go at least 250-range and above only can feel it.
Summary:
BMW: good handling, balance power, a driver's car, many 3rd party workshops can service.
Benz: luxury and comfort, ok power, not so driver's car, many 3rd party workshops can service.
Audi: everything in between BMW and Benz, but sucks at after sales and service supports.
Brand perception in Malaysia: Benz > BMW > Audi