I have flown HKG-CMB several times in order to begin a separate ticket in CMB. I don't like that route, as the equipment offers a fairly uncomfortable biz cabin. Further, you stop enroute, some days in BKK and some days in SIN. Thus, you basically have 2 2 hour flights, arriving very late at night in CMB, and leaving very early in the morning.

I much preferred my flight to Sapporo, even though in biz - and on the return I was put in the F cabin as the plane was configured for 3 classes though sold as 2. Tokyo of course offers 1st class. I'd give up a few miles to fly int'l first class.