Depending on how much she'll fly with *A, what classes of service she'll be in, how tall she is (for UA E vs. E+) and what her FF objectives are: it can be easier to earn and retain *A Gold status with BD (bmi) than with any US-based program. Downside is that if she'd fly enough with UA to get status there, she'd get upgrades - at least to E+, sometimes more. Once in a while the UA check-in agent is nice to me, especially in part of the world where they don't see a lot of BD Gold cards, but I can't count on it.