Memento to me is his masterpiece and it's one of my favorite movies of all time. Insomnia I started to like more after repeated viewings. I haven't seen Following yet but I also don't have the same impression of Nolan that others seem to have as well, even after watching Batman Begins. I think it's well documented on this board that I feel it was a very good movie, but not the best Batman movie let alone the "greatest comic book movie ever made"