moeman,

That would depend upon your flying pattern, and also what's important to you.

It's really unfair to compare the bottom tier elite status that you'll have with AA next year with the 2nd tier status that you'll have with CO if you are comped. Remember, your comp is a once in a lifetime only thing!

What is your flying pattern? Do you fly a lot of international flights? If so, AA has a far superior international upgrade program...far fewer restrictions than CO.

OTOH, if most of your flights are domestic (and EWR-YYZ are considered "domestic"), CO has the major advantage of giving free upgrades!

You get free upgrades from Day One if they comp you with elite status! So...domestic upgrades vs. international upgrades...your call!