I've only read one book by Ally Carter before All Fall Down (it was Heist Society), and I didn't enjoy that much. But I'm glad I read All Fall Down, it's a lot better, imo.
The best thing about this book is that there isn't just one big reveal, there are so many twists and turns. The story slowly unfolds, piece by piece, and I really liked it.
I have to be honest. Grace is not the most likable heroine. BUT- she is very interesting. I was compelled to keep reading to learn more about her. As for the other characters, Alexei is really annoying at first, but I grew to like him. Noah was a sweetie, I really liked him. I also liked Rosie and Grace's grandpa.
Overall, I really enjoyed this and can't wait for the sequel.