I've tried several different books on this subject (all to long and boring), this one is to the point and useful, no whole chapters on "history". Very usable.

I purchased the Linux+ Passport Book because I had great success and enjoyed reading the A+ Passport Book from the same company. Unfortunately, the Linux+ Passport book feels very rushed and incomplete.

There are many instances where the author keeps mentioning "this technology is not used anymore because the Comptia objectives are from 2004."
This was good to know the first time, but after reading something similar 6 or 7+ times, you wish the author would teach more on Linux instead of complain how outdated the Linux+ objectives are. Also in some cases, the author would mention, "you'll have to make your own decision whether to study ________ more since the objectives are of October 2004." Some parts of the book would briefly introduce a topic, and then tell you to decide whether or not you think this information is important for the test. If you want to research it more, they give you a bunch of internet links.

One bright note is the CD that comes with the book, the tests are great, the explanations are short and too the point, and theres over 160 practice questions.

If your looking for a Linux+ book I wholeheartedly recommend the Comptia Linux+ Certification Study Guide, by Robb H Tracy. The book is about 3 times bigger, but the information flows well, and the analysis for each linux objective is indepth and complete.

I bought both since they were the latest Linux+ books available at the time. Unless the Linux+ Passport book has any major revisions soon, you should save your money and borrow but not buy this book.