I flew JFK-NRT-SIN on JL yesterday and I have to say I was really happy with the Y product. Seats - legroom and space is great in Y- food was the best I've had(main meals) in coach - I had special meal. Crew is hardworking and great.
Entertainment is week - bring some of your own. My only complaint is with a special meal - you don't get the ice cream after meals

I requested for it and was finally given one after someone else declined.