If I could rate this book in negative it would be great. It is so biased not only to Sunni or Shia sect but as whole toward Islam. It seems the author is telling her point of veiw. it seems more like a story far away from truths and facts rather than being a history book. I just started reading and i was like Whatttt are you in your conscious. She made a point at some stage and later on contradicts it by telling something else. There are a lot of laseley own opinions rather than facts. And i bet not only Muslims but even those who wants to know about islam can sense it.
I would say either it's bad research or a poor try. (i hope you understand what I am trying to say)