He's incredible - some people complain that he's a little bit of a slow reader, but audio book apps usually have a speed option. He enunciates well and adds a depth of feeling to the work that can take a book that's average up several notches.
He's also the only narrator that I can name[0].
[0] Who isn't well known for other things -- Douglas Adams narrated his entire series, and some actors are also regular audio book narrators, but Scott Brick is purely a narrator (or at least, was when I last looked).