No language option in the Japanese version.
Zero load times, highly configurable, improved character portraits, graphics are slick, have transparencies, they tried to clean up what was generally a pretty ugly game and so a good enough job of it. This is probably the best looking graphical version of the game.
I've yet to try and do the Geese/Zero infinites, though Devil_Gans said he couldn't pull it off so the timing may be different or that could have been fixed in the port.
Otherwise combo timings are the same, I had no problems playing with combo heavy Kim, Iori, Terry, etc.
The only downside to owning the import PS2 version is the lack of languages for the dialog, and that's important to some people here so I bring that up.
If you just care about having it for vs. play then the import will do more than enough for you. The port is good enough that I can't see owning the PCB or AES version unless you wanted it for collection purposes. The port is that good.