i would have absolutely no hesitation in downloading it. and someone will patch the japanese version, and it will be done within the next week or so...give or take. why do I have no hesitation, well lets see:
1. the game is over a year delayed.
2. where is the online feature? if a game is delayed 1 year, you can make online work.
3. if the japanese version is done, for what reason could they possibly need 3 months more time to port a US version? we're moving into 1.5 years delayed on US shores.
but in all honesty the main reason will be the overlap. if i can have it today for free, or wait 3 months for the same thing and pay $50 for it, ill take it today. if PD tosses an online feature in for US, then hey, they'll get my $$$...i consider it a worthwhile investment in that case. but with simple things, like no 2-player garage races, etc being left out....i say boo to you PD. Boo for making us wait longer than our asian friends, boo for no online, and boo for not getting it spot on given the >1 year delay.
I should have been sitting in my pajamas christmas eve next to the fire, having GT4 drift sessions with my friend Taka in Japan, and drinking hot cocoa. Theres your reason.