Air China provide very competitive fares on the Tokyo Beijing route, undercutting ANA and JAL by a significant margin.

Service is generally not up-to the standard of other Asian carriers and the staff have a very abrupt manner on the whole.

The planes used on the Tokyo run are tired looking 757s, which do not provide the comfort of that provided by other Asian carriers. There is no personal entertainment system. Also, they look like they are in need of a good clean and new seat coverings.

However, if you are simply looking for a cost effective way to get from A to B, give them a shot and you'll save yourself significant cash.