Although I'm an experienced Unix systems administrator I bought this book to guide me through the nuances of Red Hat Linux (of which there are many) in preparation for the RHCE exam. Although the tone of the book aims it at people coming from a Microsoft background, this doesn't stop it being useful to more seasoned Unix folk.
The style is relaxed and informal, and while this makes the book very readable it can also lead to confusion, with seemingly unrelated topics following on from one another (we jump from mount options to RPM management to run levels in sequential subsections). This is not a major problem, however, as the subsections themselves are succinct and don't go into too much detail where it isn't required.
The main area that lets this book down is quality control. I wouldn't be surprised if the closest this book has come to a proofreader is a cursory spell-check. Picture captions are transposed and duplicated, incorrect commands are given as examples, filenames are mangled and all sorts of other errors are spread throughout the book. This is *unforgivable* in a text designed to put people through an exam, and for this reason alone I would recommend RHCE hopefuls to consider other options before buying a copy.