Originally Posted by ngariman
... frequent flyer points/Miles they would only really be used for trips back to Australia.
Also take into consideration how easy it is to actually use your points/Miles for flights to Australia. As AF/KL don't fly to Australia themselves, you'll be dependent on MH or KE. In general, they're not too generous with Award seats.
Consider BA, they have direct flights from LHR and are, just like Qantas, member of OneWorld. So it might be easier to get Award flights with them.