With AC you get the new Signature Suite but it will be an earlier departure, so it depends on the fortitude of your stomach.
As I have said before, the HKG route is staffed by good crews usually but it very paint by numbers. Efficient, organized, perhaps a little cold. The crew will be attentive but maybe not 100% friendly.
This is in comparison with the YVR base where you get a warmer crew.
I have not flown CX so I cannot comment on their service.
Also, that flight is usually delayed a tad (to use the Airplane 2 reference) so you may want to plan around that, if that matters