I don't think of myself as a hardcore Austen fan, nor a hardcore zombie fan, but this book pleased both sides of me.
This monster mashup is well aware of what it is and makes no effort to conceal its quirk and strangeness, which is exactly what makes it so good. It's straight-faced, ridiculous zombie action in a Regency suit, it's a jester with substance and wit and a funny hat. And it works. It largely keeps in tone with Austen's original dialogue and much of the original text, which makes it even funnier when you start reading lines about martial arts, shuffling undead, ninjas, disembowelment, vomit and some of the funniest innuendos I've seen in ages.
Look, this book is not high-brow literature. It's still quality work beyond doubt, but you'll be reading this for fun. And fun you shall have.