I was really excited about this book, finally a book that will actually instruct me on the beast we call Magento. I received the book and dived in as soon as I had some time. I do feel like I have a better understanding of how the files are arranged, the methods used and how to extend functionality. The only problem I have is that none of the code examples work, at least none that I have tried so far. The shipping module is the big one for me. I've installed lots of extensions, yet this one never worked. The author was really great and provided decent support, but in the end it was basically "bummer that it doesn't work for you". Due to what I learned from the book I was able to see the mistakes in the code that goes along with the book, but the fact that the code was wrong in the first place starts to make me wonder about all the other info in the book.
Overall Im frustrated and bummed that this book wasn't what I was hoping that it would be. The reason I gave it two stars instead of one was because I did actually learn something and it was helpful and the author was friendly. Otherwise Im tempted to try to get my money back due to all the mistakes and frustration it provides me with on a consistent basis.