When I first started reading the first HoN book, I was completely confused. The way it's written suggests it's only for immature very young teens. All the books use such childish expressions and are littered with ridiculous comments in the narrative, often in brackets (gross. eww. Whatever!) etc. Yet, the way they all go on about blood drinking and sex is surely for a much older age group? I remember reading somewhere (unfortunately I can't remember where so I don't know how credible this is) that Kristen Cast's main role in the books was to make sure the teen language was realistic. Unfortunately, between them, the authors have missed by a mile, resulting in the above.
But, they have to be forgiven. Because what they have created in the form of the HoN novels are some of the most gripping stories I've come across. And I read a LOT. No matter how terribly written these books are in some ways, the story is just so engaging. The only exception is the first book (Marked) where the beginning is very forced as the authors struggle to establish the foundations of the world that the HoN is set in. To use a cliche, I couldn't put Tempted down!
The first five books have set up this book beautifully. The story is head and shoulders above the rest in every way. A lot of significant events occur in this book. The story is more multi-dimensional than the rest, mainly because the story is not all told from Zoey's perspective. It jumps around among the other characters, also giving the advantage that the book has much less of the annoying childish narrative as I mention in my first paragraph.
So if you liked the first five HoN books, you should love this one.