Originally Posted by CO 1E
These days, I can't imagine buying a higher fare class for a domestic trip in the hopes of increasing chances for an EUA or success using a mileage upgrade (I tend not to use domestic mileage upgrades anyway - prefer to save the miles for more expensive rewards). Why not just buy a Yup or Z if available - they're usually not much more expensive than Hs?
I don't use miles for an upgrade on domestic trips--I just take my chances. It hasn't worked out too well this year either; that's the reason, I end up flying JetBlue if I have to go east at the last minute.