I think the preference between JAL long-haul business class products mainly boils down to whether you value IFE screen size (35K) or leg and foot space (77W). There's also the privacy issue -- the aisle seats on the 77W are basically right in the aisle with no coverage, while the window and middle seats on the 77W are just about as good as the 35K seats with doors.

I used to fly with small children in J under an expat package, and strongly preferred the JAL Sky Suite because I could keep them within reach, which is not possible with any other business class product currently flying between the US and Japan. The middle J seat on the JL 77W is the absolute best for a small child because it basically turns into a playpen...