I've been playing the Japanese version following my own guide. It's working great. But there is a problem: it has softlocks. Just in case you want to get the cheaper Japanese version, keep this in mind. It's not unbeatable, but save often.

The softlocks have happened in the Main Gate and Gold Hawk HQ. The music still plays and the game still animates, but you can't move. And this is supposed to be in required cutscenes. You have no choice but to reset. The Japanese version was known to be slightly suboptimal but not deal-breaking before this (with the chest opening) but this solidifies the Japanese version as the less optimal game, and this is in a game that already has problems with forced resets through no fault of your own.