I don't know which two characters were PS3 exclusive, but I'm guessing they were Crescendo and Serenade, two of the four characters I never used. (March and Salsa can also go to hell, not that I ever used Claves either).
The voice acting didn't really bother me (McDonald Miller's in there for fuck sake) the only substandard part of that game was the copypasta gameplay of it. New scenery, 2-5 new enemies, do that for an hour. Fight a boss, enjoy some cinematics. New scenery, 2-5 new enemies, do that for an hour. Fight a boss, enjoy more cinematics. New scenery, 2-5 new enemies, do that for an hour. etc. Battle was fun but there wasn't a lot of imagination or variety.
And while the character animation was very jerky and unnatural, any given screenshot of the game was just gorgeous.
My brother also said the game was very easy but I had a really hard time with some of the bosses (the ones where you had to use specific characters I never used, so I was vastly under-levelled) but any fight where you get to pilot Viola is ezpz.
PS3 version had a handful of extra content though; apparently like half a dozen new side missions/bosses/story and stuff. I haven't done the Encore yet; I'll do that once I've kinda forgotten about the game so yay re-experience. Except from what I've read Encore is fucking tough as hell since enemy stats are jacked up.