Originally Posted by
goodison
As mentioned if in J/F then AA over BA regardless of 772 or 77W. Better lounges, seat, IFE and you get WiFi, warm nuts, live TV etc.
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Is it not the case that you can use any Oneworld lounge, so that's not a real thing, the AA lounges I've been in are not great. BA Miami flights leave T3 (I believe) so the sensible will be in the Cathay lounge anyway. Lounges are not relevant to the AA/BA question.
Better seat is subjective, it's a different seat.