Having read his other book, I can't suppress the urge to compare both.
The Death Of Bunny Munro isn't near as challenging as And The Ass Saw the Angel and it certainly does not feel as well accomplished. 
This story is really fast paced, makes (almost) 300 pages feel like 190 at most despite the clutter of events and catastrophes that Bunny puts himself in, which in turn makes it all feel extremely chaotic and, in a way, makes you want to keep reading to know if this time Bunny's finally done himself in. It is entertaining, but in the way a car crash you can't look away from is.
The exacerbated humour with which Nick attempted to deliver serious topics feels overwhelming most of the time, kind of drowning the intention and goal of the story in all its absurdity.
In the end, the conclusion felt rushed and disappointing.
I don't think the book proved its point successfully and I do think it can easily be perceived the wrong way if you're not familiar with Nick's work and sense of humour.