I have to fly London - Sydney in February. I'm a UA Premier member and AA Platinum member (though soon to be downgraded to Gold I think -- not enough flying in 2000. Might be able to do the Platinum challenge later in the year).

Can anyone tell me if the following is a good way of doing this trip? I thought I'd buy a cheap AA ticket (about £200 published fare available via AA's website) and get my base miles, Platinum bonus and EUR 5,000 mile bonus. Then I'd use a QF business class award JFK-LAX-SYD for 105,000 miles. As I'd need 140,000 miles to fly QF business from LHR to SYD, I figure it's better to spend £200 on an economy ticket (which is fine for a London-East Coast sector) to NY, and thereby save 35,000 miles.

The alternative is to do the same kind of thing on UA, i.e. fly on a cheap ticket from LHR to NY (though only get the 25% Premier bonus), then spend 90,000 UA miles JFK-LAX-SYD return. Doing the same trip using mileage from London is 170,000 miles in business!

I've flown Qantas J class long-haul before and found them excellent (can't compare them with SQ because I've never flown them, but QF compare well with CX and are better, I think than BA). UA business I've only flown transatlantic (B777) a couple of times, but I've found them pretty ordinary. So I figure it's better to spend 105,000 QF miles than 90,000 UA miles. Or am I missing something? Can someone advise me if the above plan makes sense? Thanks very much.