i keep aa exp status for upgrading int'l. they have the best policies regarding pricing and vips (although 2's were much better than ow's) i keep nw plat status for upgrading domestically. they are the only major to allow upgrades on domestic award tickets, plus association with co, which i prefer to nw to travel to asia(upgrading is easier than on nw). i have dl, us, and co for no other reason than after sept 11, it was easy to (re)qualify with double status miles.