For those who doubt the 4 thing being a big deal for the Chinese, consider this article and remember that these are Chinese families in America:
http://www.latimes.com/news/local/la-me-arcadia-numbers-20110521,0,6077634.story
That issue aside, I don't like the idea. Why follow Audi? Everyone in the car world knows what the 3 Series badge stands for, even if it's getting dilluted by having so many variants. But the 3 Series is still the 3 Series and that has brand equity.