The book is very well laid-out and contains such useful information about the game and setting that you can run a session with virtually no preparation (other than having read the book and, ideally, at least played before).

My only real criticism is that the setting seems to consist of all of the author's interests mashed together. I'd have preferred a more straight-forward crime-fiction setting rather than including the steampunk and ghosts and horrors outside the cities and so forth. When running the game myself I tend to de-emphasise the supernatural elements, but I'd have preferred they not be part of it at all. It's an issue I have with a lot of RPG settings, where I love the core concept but find myself less and less interested the more elements are added on top of it.