it was completely playable for me without a patch, though i went through it a long time ago.
the godspeed boots were an interesting edition, as was richter having an alternate costume. maria is wayyy more powerful than she is in the psp version, and there's also a few additional equipment items (the alucard spear immediately comes to mind).
there wasn't any additional dialogue that i can recall, but like i said, this was years ago that i had played it.