This is a sympathetic view of the life of Muhammad. It reads like a story which has the means of sucking you in and transporting you back in time to the events in question. I honestly like this approach because it gives the story without footnotes. The drawback is that you have no source quotes, for those who enjoy such things, and can never be sure whether the sources are being properly used. The back has a short, very short, list of works that were sourced in the writing of the history. So if she is making mistakes in her presentation you either have to dig hard in the sources or already know them very well to know.
I definitely liked this book. It is in story form - narrative of his life so it reads like a fiction book rather than a non-fiction biography. It seemed to be balanced, talking about Muhammad's positive attributes as well as his cruelties and injustices. Although it had a bibliography in the end, I do generally like to see footnotes which allow me to reference specific sections of the bibliography for comparison to the source material. Kelen herself at the end says that some of her quotes are paraphrased.
Also maps showing the terrain and local occupation of the different sects of early Arabia would've helped too.