To be honest, I've just started this but I'm already hooked. The reviews I've read say it starts slowly and it does ... but there is so much to think about as the story unfolds. I like how the author makes the reader work to understand the world, the people, and the situation.
ETA: I just finished it. The last 3rd of the book was a pretty wild ride. There were some things I predicted, but also some surprises. I found the teenage characters much more compelling than the adults, even though their motivations were a little hard to understand at times. I did find the lack of consequence for all of the destruction a little unbelievable, and I wanted to know more about Ayumi's fate.
The ending made me wonder what would happen to them and to their society, wonder if any of these events would change the world that they live in.