Pretty sure you will be better off crediting to AA (unless you were keen to redeem on QF where status members may have greater availability)
If you were looking for short-haul redemptions BA would be a consideration
Edit: QR sometimes have 2,3 or 4x miles offers on own metal which could tip the balance in their favour
Does AA have a calculator somewhere on their site? I think I stuffed up the earn and only added 20% EQD to the miles which I don't think reflects the true earning? I have to calculate base miles by 5 but - government taxes? not sure if I then add 20% on for EQD. Sorry more of an AA question. I didn't see a calculator option and I don't think I'm interpreting the chart correctly.
https://www.aa.com/i18n/travel-info/partner-airlines/qatar.jsp
16248 miles return and fare was ~ $6595.60 AUD so 4928.33 USD. I'm not 100% sure as to which of these might be government tax vs carrier but I guess the biggest is the 646 and the rest are minor overall so could just take the 4928 USD x5 = 24640 to give me a ball park but do I add the 20%EQD (4928) on top to make it 29568? I did also just send SPG points to AA which should translate to 60,000 AA points ?EQD.
Taxes and carrier-imposed fees
[TABLE="width: 100%"][TR][TD="width: 50%"]Security Charge (FESE)[/TD][TD="width: 40%, align: right"]6.20[/TD][/TR][TR][TD="width: 50%"]Safety and Security or Baggage Screening Tax (WGSE)[/TD][TD="width: 40%, align: right"]6.69[/TD][/TR][TR][TD="width: 50%"]Fuel Surcharge (YQAC)[/TD][TD="width: 40%, align: right"]646.00[/TD][/TR][TR][TD="width: 50%"]Airport Departure Tax (HUAE)[/TD][TD="width: 40%, align: right"]37.70[/TD][/TR][TR][TD="width: 50%"]Passenger Services Charge (WYDE)[/TD][TD="width: 40%, align: right"]31.41[/TD][/TR][TR][TD="width: 50%"]Passenger Service Charge (PZSE)[/TD][TD="width: 40%, align: right"]1.40[/TD][/TR][TR][TD="width: 50%"]Passenger Movement Charge (AUDP)[/TD][TD="width: 40%, align: right"]55.00[/TD][/TR][TR][TD="width: 50%"]Fiscal Tax (YRVB)
[/TD][TD="width: 40%, align: right"]11.20[/TD][/TR][/TABLE]If I wasn't going to fly EY also over the next few years then crediting to QR would likely be the best option but I'm splitting myself to try them out at the moment.
I have EY later in November and looking to book either QR or EY next Feb.
Earn rates and burn rates can be poles apart. You might 12k on QF but 8k. On paper that makes QF look better (and that almost only ever occurs on paper!) but the burn rates are more significant. For 8k AA might give you a transcon in Y (it doesn't, but I'm just giving an example) whereas 12k on QF might get you an upgrade CBR-SYD. In my opinion, you're better off not comparing the earn rates so much as what each earn will get you on each airline. And you've summed it up fairly well with your QR Australia-LHR example.
It's also worth factoring in the cost of redeeming. Typically Qantas will want your first born in taxes whereas AA will be happy with a few strands of its first haircut. It's worth doing a dummy booking for the routes you're interested in using both carriers and see what the taxes are.
Remember that upgrades, while generally a better use of QF points, are also quite expensive for the cheaper fares (and not available on the cheapest fares).
If you're happy to buy AA miles, the value of which depends on the exchange rate (unless you're flush with USD), then I would credit to QF on the basis that you can always buy AA miles. You can only use AA miles to buy EY tickets too, of course.
I'm not familiar with QR's program but there's every chance you would be able to extend your points validity by crediting something other than a flight (eg. hotel, car hire).
Qantas Platinums theoretically have greater access to award space on QF flights (not on partners).
I think the only reason I want to use QF points on QR is because apart from the infrequent upgrade ie 2 in a yr domestic I don't think I'll use them on anything else so QR seemed like something I wanted to go for. The other small possibility is using QF to Asia some time.
True I haven't taken the bookings through to the taxes part. But I have to use these points on something!
If buying and redeeming AA's miles get me a J redemption with QR or EY and it's a lot cheaper (not sure how much to expect) then I think it's worth it. Alternatives being sale J fares direct on QR and EY - less hassle. I really want to fly these airlines long haul flying west from Oz/Asia until I've gone through Y, J and F ie a few years at least as it won't be frequent flying. I suspect I will still want to fly both carriers even after that and won't commit to one or the other but if it was going to be one I suspect it will be QR.
Unfortunately there are a bunch of programs that have hard expiry when it comes to points and QR is one of them unless you are platinum. You can pay to extend Qmiles to a 4th yr but that's it and they purge them twice a yr. EY there is no extension and EK you have to transfer to someone else's account with recent activity (don't know definition of recent) to extend another 3yrs.
Thank you both for the input.
EDIT: Maybe EQD is part of the status arm of the program.