Having flown both frequently, I'd pay for Jet Blue (especially if you can get a throne seat). I don't particularly like the old BE Diamond seats in business on AA because of the footwells and storage space, and I've not yet had a negative experience in Mint. In my own experience, especially on Sundays and Fridays there's very little (if ever) saver availability since those are pretty business-heavy days.

But, if like me you have a ton of AA miles and not many opportunities to spend them in the medium term, it's 62.5 isn't a terrible rate. (If you have opportunities to spend them on international travel, especially on non-BA OW partners, I'd save them for a better use)