What do you want to use these ff miles for?
FF miles are not equal to earn or burn. In discounted Y you may not get 1 ff mile per mile flown.
15,000 miles in 1 ffp may get you a longer award flight than 10,000 ff miles in another ffp. And them there is cash surcharges
Expiry can be different.
Airlines have alliance & non alliance partner's. A non alliance partner may be better
What airlines - route?
http://www.wheretocredit.com/
http://www.flyertalk.com/forum/skyte...i-sign-up.html
http://www.flyertalk.com/forum/infor...help-here.html
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