flights from the east coast to the dominican republic can now be had for $250 to $350 on major airlines

this same trip will cost you 25k ffm on united and 35k ffm miles on the other majors

for a lot of people its better to pay the ticket fare and save the miles for another trip

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you should also differentiate bewteen the value of a USAIRWAYS FFM vs another airline

a quick check on ebay is showing 25k US FFmiles from $150 to $250

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my general rule is if the ticket is less than $350 to buy it, rather than using 35k ffm, as i value the miles at about $0.01 per mile