Currently in JL F over the Pacific. JL is a slightly better choice than NH or CX. (Don't fly KE enough to comment.) Seats are little roomier and more comfortable. Seats are designed for dining together. Don't think infants will be problem. On my last JL flight I was in J, and my seat mate was a mother with infant. The CA took the baby, gave her a bottle and walked her around for 15 or 20 minutes while the mom was eating. When my kids were infants, they flew up front quite a bit. No on complained.