This books stays fairly true to it's goals of providing information to help crystal skull caretakers understand some deeper details of the skulls and how to interact with them. However, most of the material would not be understood by someone without prior experience in metaphysical modalities such as energy work, dowsing, channeling, etc. or someone who has actually owned a skull and felt that it may be activating. It is actually experienced caretakers of crystal skulls that would get the most from this book.
If you are interested in crystal skulls, and do not yet have one, then this is not the place to start. You would be better served by looking at either 'Mysteries of the Crystal Skulls Revealed' by Bowden, Shapiro, Nocerino (if you can find a reasonably priced copy), 'The Mystery of the Crystal Skulls' by Morton and Thomas (you do need some familiarity with metaphysics to appreciate this book as well), or perhaps 'Journeys of a Crystal Skull Explorer' e-Book from Joshua Shapiro. Any of these books are good starting points for understanding and working with crystal skulls.
Regarding the content of this book itself the author has presented much information that may be important but lacks sufficient grounding to be perceived as being much beyond speculation. An example of incomplete information is the scientific measurements of energy fields the author has made of crystal skulls under various conditions. Although the numbers presented are interesting the actual device used to take the measurements is never adequately described or shown. In the scientific method, which this author is attempting to use, measurements are only as good as the device. If the device is not calibrated or does not function consistently then measurements have no meaning.
The author also borrows heavily from other written and channeled sources. These sources at times provide helpful resources but frequent use of them tends to dilute the authors own unique and possibly important message. Specifically of concern is the authors inclusion of third-hand information of claims made by Harley "SwiftDeer" Reagan of the Deer Tribe Metis Medicine Society (which Harley founded in 1986). Mr SwiftDeer is an extremely controversial figure. The Cherokee, whom Mr Reagan claims affiliation from, flately deny that he is a tribal member or is carrying authentic teachings. Mr. Reagan claims to have knowledge of the legend of the infamous thirteen crystal skulls. However interesting this story is the inclusion of this claim from a generally discredited source does tend to distract from, if not slightly weaken, the authors overall message and claims.
For someone who has experience in metaphysics, and can filter out unsubstantiated claims, this book is worth reading. If you have a chance to see the author or any of the other caretakers of the more well known crystal skulls in a workshop or other setting it would be well worth your time.