They are great for when I'm flying. (I started and finished Storm Front while flying home from California last Saturday.) The parallels to his universe and yours in the Paxton Locke series are interesting. I think it is why I liked it instantly. Hopefully we'll be seeing book 4 soon?
(And I know I'm in the wrong thread for this, but I just realized that I somehow missed Z-Day Book 3? I have vacation coming up in a week, so I've rectified that situation.)
4 is with the publisher waiting on the editor and cover artist, and I'm about a third of the way through 5. I hope to have them out pretty close together.