I bought this book mostly because I read a different book (Embedded) by this author which I liked. The descriptions / reviews of this book gave me the impression that it would be funny. I figured that the mixture of alternative history and humor would make this a quick and fun read, but after only a couple chapters I got bored.
Now I'm not the kind of guy that can only focus on short stories ... I've read quite a handful of seriously deep stories with hefty page counts per book (for example, Wheel of Time, Malazan Book of the Dead, Baroque Cycle). No, this book was boring because it had insufficient or poorly written action, characters that weren't very well developed, and lots of seriously long and boring dialogue or exposition using pseudo-Elizabethan or otherwise confusing dialect.
I expected the humor to be dry (i.e., British) ... but this book was dryer than the mojave in summer. I managed to crack a smile in a small handful of places, but not once did I get an real laugh. Compare that level of jollity to, say, the Discworld stories by Terry Pratchet ... I can't get through a Pratchet story without at least one serious belly-laugh. So ... Abnett is no Pratchet, that's certainly for sure.
Anyhow, I won't say it's a bad book -- the premise of the story was good, and I really wanted to enjoy it, but it just didn't click for me. Many reviewers are fans of Abnett's work in Warhammer stories, but I've not read any of that work so I can't compare. I can say the writing in this book was quite different from the one book I did read and enjoy, so this was a bit of a letdown.