The author, S.K. Hookham, is a well-trained scholar and a lama qualified to teach these matters. The reader can be confident that this text is an authentic, authoritative introduction into one philosophical system of Tibetan Buddhism, a view shared largely (there are exceptions) by the Shangpa and the Jonang. This is not easy reading but if one has made some committment to the Buddhist path and studies earnestly, those efforts will be rewarded.
I recommend it highly to practicing Buddhists, and those aspiring to Buddhist practice. (If you're not sure if Buddhism is for you, there are other books that can help you, such as Chagdud Tulku's "Gates to Buddhist Practice.")
This view is the legacy of many generations of wise beings. May it find the readership it deserves!
This book is an informative and useful explanation of the Shentong (AKA Yogachara-Madhyamika) view of Reality in the context of a commentary on the Ratnagotravibhaga. Any serious student of Tantric Buddhism will find this very useful in reconciling sutric views and tenet systems with those of Mahamudra and Dzogchen.