I would disagree with their strategy to fly 22 hours non-stop.
For cargo, i think its ok, for passenger, i think it will be a
torture. I have tried the non-stop NY-Sin 18hours flight. all I can
say is that it is HELL, specially for economy plus passenger.
As for the fuel efficient of boeing, it will be less effective when
oil price start to fall, which I hope will happen soon.
Airbus 380 advantge is to maximise the landing right and it will be
very effective for SIA's Kangaroo route.