I would have to say AA for non-quantifiable reasons. Crew-wise, it is a coin toss- you might get an energetic and absolutely stellar one- but maybe not. UA's seat is more modern, of course, but I find that with AA, expectations are low enough that they are easily exceeded.
PS- AA offers PJs in F- also, new amenity kit (have both, and while the contents are similar, AA's has a nicer bag