I really enjoyed this story and the way it was told. In the middle of the book I was pretty conflicted about quite many things and I liked that everything wasn't just black and white. 
 I really liked the array of characters. I had my problems with Mare, but in the end I was fully rooting for her. My first impressions of Cal and Maven ended up being right, woohoo! The minor characters were amazing, too, and it was great that there were both Reds and Silvers that I liked and didn't like. I didn't like Farley at all at first, but she totally earned my respect! 
 I agree with people who say this is a mixture of many different stories. I saw elements from The Hunger Games, Divergent, X-Men and, I guess, Selection (haven't read that one though). 
 This one has a huge plot twist towards the end and I'm pretty proud of myself for knowing who had to be involved in that and kind of how. (view spoiler)[Thanks Julian for the signs! (hide spoiler)] Therefore I wasn't too shocked about the twist but I still very much liked it. 
 The ending promises that more great things are coming. I can't wait to find out what happens next!