Am not inclined to posting my flight itinerary here but just searched again for the same flights on the CA website and Alipay and the quotes were CNY2200 and CNY2039 respectively, all in.

This means a price difference of CNY161, a bit less than what I got.

The CA price has remained the same and the Alipay quote was higher.

Difference is you get immediate eticket issuance for CA and at least an hour's wait (and worrying) for the latter. Till now I still have yet to get my eticket number, and in response to 889, no, you don't get told there would be a wait. They do offer prompt tix and I suppose you'll just have to turn up at the airport counter and expect your details to be in the airline's system.

You can probably try to see if this price difference is replicable with a few searches of your own.