I heard a lot of really great things about this book, and author, and while I could see it would be an enjoyable book to read aloud to children (because of all the onomatopoeia, and silly jokes) I felt it really faltered in depth of emotion. It had emotional moments, but there were a lot of deaths that felt like they didn't really impact the main character in a significant way, and it felt like the only real growth he had was not being "sickly" anymore.
Over all, I can see how a child would enjoy it, but I wouldn't read it to a child of mine, and definitely wouldn't compare the author to Roald Dahl.