To be honest, I was more interested in the origins and contexts of the fairy tales themselves, found at the end of my edition, rather than the story itself. However, reading how Connolly incorporated and revised the stories so that they flowed within David's story made me more appreciative of the book as a whole.
David's story is interesting, and the characters that he meets are well-fleshed and entertaining. I enjoyed the re-tellings of familiar fairy tales (Snow White and the Seven Dwarfs was a particular favorite, and the most light-hearted). I found the tale compelling enough to keep me reading, but it didn't keep me on the edge of my seat. And until I read the notes at the back of the book, I didn't fully appreciate what Connolly had done.
So, while this is a story that can be enjoyed on its own, I highly recommend buying a version that contains the notes at the end (entitled "Of Fairy Tales, Dark Towers, and Other Such Matters") to tie everything together and give the story more depth.
3 out of 5 stars.