the chinese company (C) will do most of the development, marketing and sales, and the market is in China.
I don't mind estabilishing a Chinese company, just jumped ahead worrying about exit strategy.
Another issue is that if the control of B over C is through contracts, there will be some trust issue because the entire operation is under the watch of C, in which the American partners do not have a share recognized by Chinese law. Since you've worked on some deals like this, you must know how guys in China behave (thinking 3721).