aa can get you to the carribean & to mexico & europe....i do suggest that you look at aa & ua's partners, both for earning & redeeming mi's...i am not really familar w/ua, only fly them 2 or 3 times a year...put your wish list together & match it w/ both airlines and their partners, it might help in your decision...also spend a lot of time following them in these forums...good luck!