If you want to get some idea just how important China has become as a luxury consumer market you don't have to go further than the recent Beijing auto show.

What started out as a low-key event in 1990 has grown into the biggest and most important stage for the world's auto makers, especially those at the luxury end where models are tailored to China's affluent.

Wander the streets of Beijing and Shanghai and you are sure to see BMWs, Mercedes-Benzes, Porsches, and Ferraris - just about any top-end auto brand that comes to mind.