This series of books has a great ending, as good as celluloid can offer. I was drawn in completely and surprised at some of the changes, but more importantly, I was fully satisfied with what was offered and promised throughout the arc. I can't understate the importance of this. Any great buildup should have a great wrap-up, and this book fits the bill. 
 I honestly would like to read a much longer follow-up, even without the need for a clever story or great tension. The fact that Mr. Howey was able to make me want to stay and see what happens to those who survive, or even see what happens to the other silos, is a testament to the great world-building. I'm just not tired of the whole experience. I'm not willing to move on to a different book. 
 They're good novels. I didn't like the Shift novels as much, but as a method to world-build, we really couldn't do without them. Dust, on the other hand, pulls everything together in a damn fine way. Promise? Delivered.