After flying first class on United Transcontinental flight 1735 Newark-LAX on a 757 and American Airlines transcontinental flight 118 LAX-JFK on the new Airbus A321T, both in June 2014, I have a few comments that may help you planning your next trip.
Check-in: the first class check-in at LAX was a breeze with American. We were invited to the first class lounge where we had breakfast and then escorted to our seats on the plane. A real VIP feeling throughout the process.
United, on the other hand, was a nightmare, with long and disorganized lines, rude personnel, computer glitches, and if you are on first class, but not flying international, you are not welcome to the lounge. Great job, United, for making me feel so special for buying your first class product... for the last time!
Onboard: American bought new planes for this route and they have a three classes configuration, therefore the first class is a 10 sitter cabin with a 1-1 configuration. A lot of space and first class service, with a menu for food options, large pillow and extra large blanket, toiletries bag and friendly flight attendants. Wifi during the flight.
United fly the old Continental 757, with updated first class seats. Cramped feeling since the seats are too large for the small space on a 2-2 configuration. No pillow, no blanket, no menu, no wifi. A tray with tasteless eggs and fruits. The flight attendant laugh when I asked for other food options and herbal tea, and she added: "Wrong airline". You can say that again, lady!
Both offer the same kind of Entertainment options. Movies, TV shows, games and music. I tried to connect my ipad to the system but in neither airline it worked.
Without a doubt, American has the best product for transcontinental flights today. Virgin America is my second option, since it started the trend that now every airline tries to emulate. United was a disappointment in every category, and with all the competition out there, it's no longer an option for me.