Thanks. Yeah, that all makes perfect sense. Just to clarify one thing, 80-90% of my flying is either NYC-SFO or NYC-YYZ. I've only had to do YYZ-SFO once.

To my view, upgrades on NYC-SFO are very meaningful. Upgrades on NYC-YYZ are close to meaningless (it's about 45 minutes flying time, and I don't drink .

I understand UA doesn't offer CPU's on transcons anymore. I suppose I should ask around to see what luck AA EP's have had getting upgraded on transcons. Beyond that, based on your helpful replies my choice seems pretty clear: I'll have a better experience flying AA, but I'd have more routing options on UA (AA doesn't have direct return flights from YYZ past 5:50p and can't get you up there direct before 10a, whereas UA/AC have seemingly 20-30 departures per day...similar stuff on NYC-SFO although I'm usually less schedule-sensitive on that route).

I may just stick with AA, see what my transcon upgrade rate is at EP and, if it's zilch, do a mid-year challenge to UA to get better schedule flexibility.