I flew UA NRT to LAX so it's close enough. The 747 looked very old. Standard projection/TV IFE. The IFE is actually good because it's timed nicely and is never off for more than 1 hour untill the last 2 hours of the flight. Chicken or Beef and breakfast. Old flight attendants, good service. Have a nice flight.
I flew UA's 747 a couple of times and it was always a good experience.
Food was alright, F/A's were friendly, on the 747 you do not however have a personal TV (at least not in Y).
Seat pitch is a little tight but I am 6' 2 so I always feel a little cramped in Y
enjoy your flight