Join Date: Nov 2011
Location: The Frozen Tundra
Programs: Former AA EXP, DL PM, BAEC Bronze, SPG GOLD, Marriott Gold, Hilton Gold, Hyatt Platinum
Posts: 159
Just got back but only had 6 hours so stayed in the airport....
1: the JAS Premier Lounge shows as 24hours in the website. Unfortunately it is not. It closes at midnite and reopens at 04.00. There is a shower, but make sure to take shower sandals . Ask at the bar for a towel.
As for seating - I would suggest asking for a seat in rows 15-20 on JAL. I did an wasn't asked for additional money for premium economy.
Speaking to lounge access in NRT. I visited both the Sakura and Admirals. I found the Admirals to be a bit better with food/beverage selection and more space. The Sakura was nearer to the gates both airlines use.