I still have not read chapters 15, 16, 17, 20, or 21 but the last two are not related to the exam anyway. I also have not yet taken the online mock exam. When I finish these, I'll submit my official review to the JavaRanch Bunkhouse. I've not settled on a final horseshoe rating, but as of right now I'm pretty certain it will be an eight or nine out of ten.
I really like this book. It is very well written for a book not invaded by a team of editors. It flows as if you are having a conversation with a single expert. I've never seen that done well in a technology book before.
The book claims to not be intended as a beginner's book but I believe the author did well enough to explain basic concepts well enough that a rookie could study with this companion just as well as any other.
That said, the more experience you have, the more you'll appreciate the layout of this book, as the information is very structured with little foofoo noise. This structure is especially helpful for learning class APIs, the web.xml, and standard actions. Most exam-sitters will skim through study material a couple extra times during the final week before taking the exam and the SCWCD Study Companion is certainly the best book on the market for such cramming... er, reviewing.
The weakest area of the book is in Design
Patterns, which for the most part isn't strong enough on its own to guarantee a perfect score for that topic on the exam.
Each chapter follows with about fifteen superb questions. There is a definite purpose behind each question. They help to enforce what important points
you should remember from the chapter and what silly (though important) tricks to look out for in the exam. You can tell that the author put a copious amount of time into writing thoughtful questions.
The question most people will be asking is how this book compares to HFSJ. It's smaller and easier to carry. I find that, though there are fewer pictures and jokes, I can make it through more topics before my brain starts to hurt. I think this is because the high level of organization makes it easy for my brain to sort. HFSJ may be more fun to read, but HFSJ usually makes my brain demand frequent timeouts to defrag all the information. The Study Companion makes a better reference book, a better book for subsequent reads, and is much easier to transport between work and home.
If you can afford two books, definitely get the Study Companion and HFSJ. If you can only afford one, choose the one that best fits your style of learning.