Fly TAP, not only because you have a direct flight, because it's always interesting to try an airline one has never flown before. That would be a great idea, that's what I would do if I were you. I don't think TAP is any worse than an other carrier, you'll like it and like Mirage is pointing out, they have a modern fleet except the A310. From JFK to Lisbon, you'll most likely get an A340. Tap is going all Airbus, their modern equipment includes Airbus A319/A320/A321 and A340 aircraft. Have a nice trip.