Not quite what I expected when I started. I liked Ari generally. I think she was a realistic depiction of a confused 17 year old. I also liked that her background gave her a plausible reason for knowing how to fight, how to defend herself, since that is a key point in the book (early in the book, she defeats someone who is trying to kill her and recovers a knife; this knife is important later in the story).
It didn't strike me as realistic, however, that she would form such an instant attachment to the band of kids that she met in New 2. She has had a hard time in the foster care system, and a history of emotional and/or physical abuse does not generally result in someone with an open and accepting personality.
I look forward to the next book, although I was unable to find any information on when it would be out.