I dunno, the concept was cool. On the other hand, every character had about the same personality, which wore thin as the book went on. It also suffered from what other reviewers have (accurately) termed a 'B-movie action plot' that was both shallow and predictable. Until this, I had been generally enjoying this book. It wasn't mind-blowing, but it was decently fun. Scalzi could have gone further, developed more and made something truly unique and worth recommending. Unfortunately, this just fell short.