My wife and I are flying from Hong Kong to Beijing on air China, and then connecting to United on the way back to the states. We have about an 2 1/2 hour layover in Beijing, but I am concerned that without a visa I will have trouble.

For example would air China let me board from Hong Kong to Beijing because my connection is on United? It is on the same reservation, But since I am on different airlines, what I have to clear customs? Any advice? Should I just get a visa? I chatted with the airline representative on the phone, and they seem to think I was okay, but neither was sure.