<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by pegasus8228:
for your situation, the main benefit for AA is the 100% bonus miles when flying AA.
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In my experience, this 100% bonus (as well as credit towards "earned upgrades" -- ultimately good for another 25% bonus) applies to all flights on AA, on oneworld carriers, or on Alaska Airlines (especially handy for west coast connections). So this is a major bonus (and, as I recall, a major differentiation between AA's partnership with oneworld and UA's with Star... though you should check this if it matters to you).