Originally Posted by
dmac7273
Unless you find yourself low on domestic upgrade lists, probably no reason for Reserve over AMEX Plat unless you need the bonus MQMs or wants the tie-breaker over other DMs who don't have the Reserve card.
And on top of that, fare class is a tiebreaker among DMs on the list before the Reserve card. So even if you're a DM who's low on the upgrade list, if you're low because you bought a cheap fare; having the Reserve card is not going to put you on top of the list. Priorities are listed
here.
It's impossible to know without Delta's data, but I'd say it's probably safe to assume that the Reserve card will generally only bump you maybe 1-2 spots on the upgrade list at most, and very often it may not bump you at all (if there are no other DMs above you in your fare class). Not to mention that sometimes, even if the Reserve card moves you up a few spots on the list, you may still not get the upgrade with the Reserve, or you might have gotten it anyway without the Reserve. So the number of times that having the Reserve card would make a difference between getting the upgrade or not would be very small.