A quick question that might help provide a more accurate answer is how many QF points do you already have? If you don't have many, then starting again in the AA program may be attractive. But if you already have lots in QF, plus earning more via credit card etc, it may be less attractive to split your earnings between QF and AA.

By my quick calcs, I think you will end up with just under 17,000 QF points from that itinerary. With AA's Plat Challenge, you will definatly make plat and with the miles earning on the AA flights, you will end up with way more than 17,000 points. Perhaps Dave :-: Noble can tell us exactly how many AA miles.

And remember that for flight redemtions in Australia, AA's miles are pretty good value.

You might also get some AA upgrades on the AA segments, which you won't get on the QF program.