I don't like this book. I don't really think there is any reason it needs to exist.
Pros: His chapter on formalism is good. I like that he takes an axiomatic point of view. For those that need it, his math interludes are helpful. I enjoy his historical chapter on quantum a lot (chapter 1).
Cons: It is too mathematically light and attempts to cover too much material. It is a book on quantum mechanics, spectroscopy and computational chemistry all mixed into one text. I don't like how he goes about making an analog between the classical wave equation and the Schrödinger equation.