I don't know. It would depend wouldn't it? I just know what I paid and what I got. 2 first class ANA JFK-NAR, one way business UA EWR-HAM, one way business TK JFK-IST plus several other flights in Asia. I can't really fly Coach on long flights but I probably would have settled for business if I were paying my own way. Life Miles seems to have great deals and I got 150% bonus when buying. If I were paying to go to Asia, I'd have taken SQ 25 JFK-FRA-SIN
I've bought plenty of Lifemiles myself, and they do have great deals. Not quite as good as they used to, between the increase in number of miles needed and the closing of several massive loopholes, but still quite good. I've flown F on Star Alliance carriers at least four times using Lifemiles. But I would never pay out of pocket what they wanted for my flights
. I've also flown every carrier in oneworld in F other than QR, including 4 times with CX in F and 7 with QF in F (and just booked my 8th QF F flight), but again I wouldn't have paid the ~$5-10k each for each of these.
I'm basically saying, you didn't save $41,750. You saved (amount you would have paid)-$8250 (cost of Lifemiles). Now, you might have used Lifemiles to pay an economy/premium economy level price but actually flew in first class. This is generally how I view it personally.
The issue is, if you value the first class flights at their face value, then buying miles would make sense even at regular price (assuming award space) 99% of the time. I'd much rather buy 145,000 AA miles (at roughly $3000-5000 depending on the promo) and fly QF F round trip to Australia from the USA, rather than paying $10k-20k for them, as an example. Just trying to help you arrive at a point where you can best decide if it makes sense to buy the UA miles or not
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