I flew through this book fairly quickly the first time I read it and when it was over it made me keep trying to find more content on the next page (click, click, click!)...sadly with Kindle books you don't know when the end will come and extra clicking doesn't make new content magically happen.
I wanted more! So I read it again, more slowly, and found I enjoyed it even more. The characters are diverse, interesting and, developed. The world and magic are deep and rich. If you like math/science you get an added layer of goodness in the 'magic' system. I highly recommend it :D (It also has cool things like naval air ships and werewolves.)