The voice acting isn't really bad, it's just the localization team didn't bother fixing the mixing (unintentional rhyme, heh). The reason why the mixing is messed up is because the timing for character's speaking was only properly timed for the original Japanese voices, and the localization team didn't bother changing the triggers for when character speech is supposed to become audible, resulting in characters sometimes talking over one another in English, where as in Japanese they avoided that problem.