I jsut came from there (currently sat in the Pier at HKG) and I really liked the AC at NRT. I had a fantastic shower. The beer selection isnt great and as I was trying to not drink for 60 hours straight on this trip I didn't sample the wine
I have been to the CX lounge before in the older terminal and it was a travesty.
TScharke has been to the Sakura F lounge and wasnt blown away.
Used the new JAL F lounge on Sunday. I thought it was quite nice, lots of staff, massage chairs, selection of hot food and good quiet areas. Not that large. It is directly across from immigration.
As a a OW Emerald, you can use the premium entry to security after checking in, if checking in at the A end of the hall, the premium entry is off to the left of where 'the others' go through, on the side. Not that easy to see at first.
New CX lounge is much better than the old one, but very standard.
There is a similar thread being discussed at the moment as well. This is what I said on that one:
I fly to Narita a fair bit and I agree with jasonja3 - the Qantas J lounge is very ordinary. The JAL F Lounge is a great improvement on their previous one and is the one I use. It has a very good food buffet and well stocked bar. It isn't as good as the Melbourne and Sydney Qantas First lounges, but it is still a nice lounge to relax in before your flight.
The new Qantas J lounge is more conveniently located, as it is right next to most of the gates that Qantas uses. But its food and drink selection is limited and I've often found it to be very crowded.
Even though the JAL F Lounge is in the other terminal, the shuttle ride only takes a few minutes so I don't even bother using the Qantas J lounge anymore.