After reading a number of the negative reviews, I was hesitant to buy it. However, it still sounded interesting so I read the sample and that led me to get the full book. I am very glad I did. The book is a good read with good character development and significant suspense.
One or 2 reviews was very critical of the use of the F... words (F... and F...ing) which occur on average about 2 times per chapter. Contrary to the one review, they are not in front of the child that often and if you live in the real world, the phrases they are used with are actually very common (i.e. What the F...?). Although I do not use the word myself, it IS the way a large portion of the population speaks and and sounded perfectly natural in its use throughout the book.
As far as the story jumping back and forth between the thoughts of the main characters, each view DID contribute to the plot development and even more so to the character development.
There was a section of the book that did have quite a bit of sex involved (although not what I would consider graphic - much less so than a typical romance novel), but it was significant to the development of the characters and their relationship with each other as well as how it fit in with their past.
In summary, if you have grown up in a sheltered environment, do not read this book (it might offend your sensibilities). Likewise, I would not recommend it for pre-teens. However, if you don't mind a book that reflects realistic personalities, I highly recommend this read!
I just finished it and am now getting the next book in the series that I am looking forward to reading (thankfully it is already available so I don't have to wait).