<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by TransWorldOne:
The problem with mileage upgrades is the need to fly on exhorbinant H/K/Y fares or pay an asinine "service charge" to be allowed to use them.
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...and also that you cannot get an confrimed upgrade in advance. CO's domestic upgrade policy is indeed quite generous, but their international upgrade policy is awful. This is my (and many others) biggest beef with OnePass. If the DL FF flies internationally and frequently uses miles to upgrade, he/she should stay put. CO's international upgrade policies stink.