The FC Lounge is really quite nice. The Red Suite in the back is very private; when I was last there the lounge was pretty busy but nobody ventured into the Red Suite. It has a champagne bar overflowing with Laurent Perrier and (for whatever reason) a very upscale shoe shine salon. (I don't remember anymore what the NRT FC lounge is like so can't compare.)
Here's the Japanese language page for the lounge:
https://www.jal.co.jp/inter/lounge/hnd_first/
and here's the food menu (enough in English so you can get an idea). It looks like some sushi is always available, though the menu is limited and nothing like what you'll get in The Wing or even the Concorde Room:
https://www.jal.co.jp/inter/lounge/pdf/first/food.pdf
Agree with the other posters that you'll get a better meal and massage in Tokyo...