I've heard that ESPGaluda II was their last region-free game. GIven the localization of Death Smiles, I think that might be the reason.
Also, the limited edition comes bundled with the OST composed by Manabu Namiki, Noriyuki Kamikura, and Yoshimi Kudo. Apparently it also comes with a voucher for a downloadable arrange album, but I presume you'd need a Japanese 360 account for that.
Arrangers as follows:
Yoshino Aoki, Kenji Ito, Noriyuki Iwadare, Ryu Umemoto, Motoi Sakuraba, Manabu Namiki, Michiko Naruke, Motoaki Furukawa, Yack, wasi303, TECHNOuchi, Mitsuhiro Kaneda, Masaharu Iwata