Do you commute? If so, do you plan to continue commuting for the foreseeable future? If yes, I'd consider FedEx just on that alone. If you live in base, or plan to move to base, that would be a tough call. Lot's of variables... how long you've been there, do you enjoy the type of flying, etc.

Lots of us have left one of the big 3 pax airlines to join Purple for a variety of reasons. I've met a few from AA. There are pros and cons with each, as with an airline and in any profession.

Aside from pay... I think it would be wise to consider: commute, type of flying, progression (you won't get to the left seat of a WB faster anywhere else), retirement (which as of late is TBD), culture. Not in any particular order.

One thing to note from my relatively short time here. There's a pretty HUGE difference between being junior at Purple and being senior at Purple. Moreso than any other airline I've worked at. So consider that. I know AA as LC reserve with 117 rest rules which makes being junior somewhat more palatable. Once you gain a little seniority here, I can't imagine an easier way to make a really good living.

Just my .02. Good luck on your decision! I say go to the interview. Can't make a choice until you do that and get an offer.