Not having the words match the mouth really takes you out of the experience. I know you said you weren't talking about anime, but still, in that case the mouth matching isn't quite so obvious. It really depends on what anime though. For FullMetal Alchemist I felt the english actors were far superior, for Naruto . . . not so much. Japenese were far better (though not all of the english actors were terrible [Kakashi]).