This was the perfect ending to the perfect series. There were a lot of extremely complicated, multi-layered things going on in this universe, and somehow all the threads got tied up in a satisfactory way. All the mystic time-travel-y underpinnings of the series became a perfect closed loop that actually made sense. Aside from an exciting plot, the prose really sings.
_Molly Fyde and The Fight For Peace_ also successfully dealt with the thorny problem of what to do with your young characters who have an epic love but are still teenagers yet have been through so many hair-raising adventures that they are almost like world-weary old people. If you found the ending of the Harry Potter series a tiny bit cloying in terms of the way it displayed the characters living happily ever after, you will find the approach Hugh Howey takes here a welcome antidote.
If this series is new to you, you better not jump in with this book because it wouldn't make any sense. Start with the first one, _Molly Fyde and the Parsona Rescue_, which is a fairly straightforward space opera. But as the series goes along, it becomes deeper and bloodier and picks up more characters. My favorite character in the whole series was Edison, who is this big creature who looks kind of like a panda bear and speaks in a ridiculously stilted and technical way (like, "My exuberance overcame my ability to forgo immediate gratification," when he hugs his friend too hard.) His dialogue usually made me laugh. It was over a year since I read the previous book in the series, and I was worried that I wouldn't remember what the hell was going on. But everything came back to me vividly as I read.
Now, about some things that a lot of people don't care about but I do. The book was attractively packaged and nicely laid out. I came across maybe two misspelled words, no big deal. I liked the cover a lot, but my girlfriend thought it was really strange. "Why is a baby playing with a wrench set? That makes no sense." You actually don't find out what the cover means until almost the end of the book.
I would recommend this series to people who like Scott Westerfeld's "The Risen Empire" books or pretty much any kind of thought-provoking science fiction. I was a little bummed when I finished this book because it was all over, but at some point I will go back to the first book and start again. For some reason it's more satisfying to be a fan of a great series that no one you know has ever heard of than it is to be the ten millionth person to like "The Hunger Games." But it is a little unfair that the rest of the world has been living in ignorance about Molly Fyde, so let's not keep this series a secret.