I have been pleasantly surprised with USAir and suggest you consider their FF program. They are the only major airline I know of that gives you 2 System Wide Upgrades for qualifying even at the Silver level- 25000 miles.
If you want to use or transfer your miles, here are 2 suggestions.....
1. If you have the miles now, use a 15000 USAir shuttle award between DCA-LGA, LGA-BOS or DCA-BOS.
2. If you have a Hilton HHonors membership, laundry your miles throw them. The equation would be:
12000 US miles = 24000 HHonors Points = 6000 DL miles
Numbers above are just estimates. Like a tshirt in hot water, it will shrink but at least you won't lose the orphan miles either. Many happy travelers have passed through the Hilton Orphanage.
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"Fly me to the moon and let me earn alot of miles."