Not sure how to rate it. I started it at about 5:00 one evening and stayed up until I finished around 2:00. It certainly kept my interest. I loved how Tris grew. I liked Four's story. And Caleb's. And the parents, even. I know what faction I'd be in. Candor, no question. I think with a trilogy, if I like it more and more as I read (like Hunger Games), I then rate the first book higher. Guess I can always reread after the next 2 are published and reevaluate. 
 Alright, just reread it. I liked it a bit more the second time around, but was bothered by something I can't seem to pin down. Still not sure what it is. But...whatever. It's a 3-star book. I'll read it again someday. The end.