The ending was good, and I won't spoil it. I give the entire trilogy 4 stars but not this book only because the last third of the book was slow and hard to get through, as if the author didn't know how to end it.
The first two books I could not put down. Would definitely read the series again.
One troubling thing about the series is its utopian nature, that somehow humanity could escape itself on Mars. No, I think the troubles with humanity will follow wherever we go, maybe because those troubles are simply part of the human experience.