We did this last Xmas, flying AA in both directions. For the JFK-LFR sector, we really enjoyed AA (having flown BA on that route many times) for two main reasons:

1. The flagship lounge is really good - great place to relax and enjoy a decent (buffet) meal before the flight. Food is much better than the BA lounge, IMHO.

2. The AA seats are very comfy for sleeping, as they have lots of space. Much better than BA standard, but I’d say 62A/K on BA still pip it. These weren’t available for the flights we looked at.