10 stars
if you want to know which member of the "who is who"
shagged with whom and when
10 stars
if you want to know which member of the royal family
talked to the author when and how often
25 stars
for the author's self-complacency and overestimation
3 stars
if you want to learn something about Camilla's family background
2 stars
if you want to learn something new about the PoW and the DoC
1 star
if you like reading entertaining and well written books
0 stars
if you happen to be so silly - like me - to have bought this book
minus 10 stars
if I will ever be so sick to buy another book by this author
So all in all, that leaves very very positive results for the unbearably pompous and self deluding Gyles Brandreth and you will learn a lot about this gentleman, more than you ever wanted.
Unfortunately, the "first substantial, authoritative biography of Charles and Camilla and their relationship" is an utter failure.