Overall - This was a very solid story that I enjoyed reading. I found the ending, however, to be a bit lacking.
I enjoyed the balance of action and drama, and was somewhat surprised by the details of the big secret. I found the characters likable (or not likable as intended) and sufficiently developed. I think perhaps some of the flash-back parts may have been unnecessary (though not terribly distracting), but I really would have liked the ending to have been longer and more detailed.
I got this as a free kindle download and there were a few editing errors but they weren't so frequent or egregious as to be distracting or unbearable.