Keen to hear Carfield's perspective as well.

I used to fly both JAL and SIA in economy quite frequently. I would say they are on par i.e. both are among the best economy class products in the industry.

I really like JAL catering, and their 787 economy cabin is 2-4-2 (Unlike other carriers who do 3-3-3). The JAL 767 is 2-3-2 with a refreshed cabin product. Cabin service on both is very good. I prefer the JAL lounges to the SQ lounges.

SQ's IFE has a much wider programme selection and they have complimentary wifi on all their flights for Krisflyer members. I believe JAL is also introducing complimentary wifi, but I don't know if it is available on all their flights to Singapore.