How about staying in a hotel?
I came from Beijing originally. Timeshare is definitely in its infancy in China. Acutally I am not even aware of its existence until I saw some resort listing on the II directory. Granted I never stayed in one of those properties since I still have a home in Beijing, I would advise you to stay in a reputable hotel instead.
Because not many people speak English there, if you choose to stay in one of those timeshare properties, there is a chance that you might not even be able to communicate with the service staff. I don't know which properties are listed with RCI. For the one listed with II, I know it is just a apartment complex that's also available for long-term rental. It's definitely not the timeshare you get used to here in the U.S.
With all the good food in Beijing, you really won't need a kitchen as in a timeshare. You can easily find a hotel in a downtown area or a location that's easier for touring around. For those so-called 'timeshares' in Beijing, I am not sure if the location is ideal for tourist.