My alternative is to use the award ticket, SIN-HKG-SFO, with 205K miles and it has availability than going on economy plus on SIN-LAX for 15 hours-seats are uncomfortable for that long of a flight and the service is pretty bad on United economy compared to Qatar, Etihad, Emirates, and other top tier airlines. Plus the toilets are also generally not that clean on UA but a notch higher than Air India.