I dont know if Whale is still working for Skymark but 3 or 4 years ago about 15 guys from beautiful Hawaii came at Skymark and if I am correct only 2 are still there and about 30 expats came from Jal (B747 captains) and already half of them are gone
If you really need a job and you Think you can cope with the system then go for it
The aircraft are almost new, well maintain,and the peoples in the office are quite nice,and Japan is not a bad place to live as it is safe, and clean
The problem is JCAB, and also the owner who can reduce your contract without consulting anybody ,and d ont expect any help from your agency (any agency)
And also you fly often 2 captains together. When you are 2 expaxt it is nice but when you fly with an ex JAL B747 Captain you become a second class pilots