AA as my backup to AS has worked splendidly for the last two years since I tubed UA when they took away most of the benefits of being a lower tier elite.
Got on AA's 100,000 mile MC promo (need to spend a bit more to get an add'l 10,000 EQM). Route map, esp down to Caribbean and C. and S. America works great in combination with AS for vacation/mileage runs in J.
--mcz