I would definitely suggest checking with Chinese travel agents--it's not unusual for us to find a better deal that way than via united.com.

Forget SHA (I assume that's the Hong Quao airport in Shanghai, it's been long enough I don't remember the code), that's now a domestic airport. International flights go to PVG. It's a much nicer airport anyway.

Air China in theory has some cheaper flights but to date I've had no luck actually getting any system to actually let me book the flight. It seems that they have a route but no actual service.