I was given a gift card to spend at China Marriotts. Having never been there (but willing to go!), I'm a bit lost.

I see Marriott has properties in the following cities:

Beijing
Chongqing
Foshan, Guangdong
Guangzhou
Hong Kong
Sanya
Shanghai
Suzhou
Teda, Tianjin
Tianjin
Wuhan
Wuxi

I assume Beijing, Shanghai and HK are a must, what about others? And how long would you suggest staying in these?

I'm interested in history, culture (cuisine being part of it), local attractions; I'm mostly urban person but if sidetrips to scenic rural areas with public transport (hate taxis with passion) are available, that's fine, too.

I can spend a month or even a bit more on this. Thinking about going this fall, when the olympic craze is over and the weather is cooler.

Any thoughts?