I´m not sure about what of them are my favorite; these one, in the game, were from Warlord Games (mine) and Brigade Games (those from José Antonio). The white metal figures from Warlord Games are full of mould line, blobs, etc. but they have a really cartoonish look and are not bad when painted. Those from Brigade Games are really fine and full of detail, and really clean castings.
In this moment, I´m using those from WG to create my platoon, with their metal figures (but I´m going to need some plastic ones for the light mortar teams...).
The USMC platoon is going to be a bit more complicate...
WarTime Miniatures from Australia have plans to have Japanese figures for their "Australians in Kokoda" range of figures.