The F section is nothing to write home about either. In my opinion, no reason to arrive early at JFK.

At NRT, you can also access the CX, QF and AA lounges along with the JAL lounges in the main and satellite building--but JAL F in the main building is in my opinion the best. Make sure to put your name down for a 15 minute massage as soon as you get to the JAL F lounge (if you want one, of course). They fill up fast.