The baggage thing was big for me last year. I was pre-emptively moving a bunch of possessions permanently back to the USA, and being able to take for free, 50 kg per trip through Asia (I was routing through BKK) plus 3 free checked bags on the TPAC and domestic USA side, x each of 3 trips added up to a big cost savings. I think the other benefit moondog didn't mention was the lounge access, even if flying Y class on a *A carrier. China's airports might not have the greatest lounges but they also don't have the greatest general gate area seating (or seating, period) and at least it's less hectic waiting out your time in the CA lounge.