I worked through the most of this book in explicit detail (the only way to get the full benefit, in my humble opinion), and, while it was very good at teaching the methods for deriving and computing Feynman diagrams, it often sacrifices pedagogy for explicit calculation. For instance, while there is a brief discussion of representations of the Lorentz group, the book gives no indication of how to construct and work with fields of higher spin. Also, I found their discussion of the LSZ reduction formulae rather impenetrable. (Their discussion of BRST symmetry, in contrast, is very readable and easily understood.) So, while I would recommend this book to anyone who wants to learn to do calculations in quantum field theory, it is imperative that they supplement this book with other sources that treat important topics, like the CPT theorem, general representation theory, and non-perturbative phenomena (which are barely mentioned here), in detail. (Also, there are a rather large number of unfortunate typos in the first edition...)