Book the 6:40 flight on AA... We've taken that flight the past 2 trips and will again in March. You will have so much time to enjoy WDW once you get there that day! Also, from my experience, that is a great fare and I would snap it up. If anything, it will probably go higher as you get closer and closer to the date of your trip. You can keep watching the fares and IF, for some reason, the rate goes down... you can always contact AA and notify them. They won't refund your money, but they will issue vouchers for the difference that you can use on a future flight. (I think they give you a year to use them.) My DH will book flights for us and then watch them like a hawk... We've gotten $100 worth of vouchers just on the last 2 trips we've taken because the fares happened to go down one day. We're going in March and paid around $750 for the 3 of us (Spring Break week)... If we tried to book those exact same flights today, it would be $2300. I'm glad we bought them when we did!!