Thanks all. Appreciate all of the feedback. I've been googling results on FlyerTalk for years, good now to be official.
Sounds like my flight will be a solid choice so I will stick with it. (The other half decent option that came up is on the same day an AA-code share with JAL from JFK to Tokyo to ICN. The JFK to Tokyo appears to be on a newer 777 but is a JAL plane I think.)