Flown the route on both. KA has good IFE, newish seats, great crew, and good catering (with Haagen Dazs). CA is a bit of a lottery. If you get a newer plane, there is AVOD. They also use a wet leased Air Macau plane on the route with no IFE. Catering is a bit worse than KA. Overall they are both decent airlines. On such a short hop in Y the service doesn't matter than much. I would say go by schedule.