Originally Posted by
MSPeconomist
If it's really only US$8, I'd do it, even though special lines and lounge access are unlikely.
Class J is not business class, so no domestic lounge just on its own. However, your same day international business class inbound boarding pass will get you domestic lounge access though. (
https://www.jal.co.jp/en/dom/service/lounge/nrt/)
You do get priority boarding, but that is rarely an issue in Japan (no grabbing of carry on space!).