Actually it's not animated at all, what they do is record the whole thing in the normal way, then paint over the film. It's actually quite different from animation. I didn't think the film needed the whole rotoscope thing, and I am not entirely sure how much there is "to get", but I agree with your rating.
I just watched The Silence of the Lambs - after seeing Jonathan Demme's Neil Young movie. I's forgotten how creepy this movie is, and how influential it was on movies like se7en. 8/10