It's very different in tone and style from His Dark Materials (probably published before it? I came to Northern Lights as a kid, via his children's books) It's short and sinister and fun - I think it's probably most similar to the bit of Subtle Knife with the world where only children survive the ghost-things, but with more of a sense of humour. My biggest recommendation would probably be to find a page or two of preview and see if you like the tone/style.