We have 90 minute classes, so it took us six days to listen to the entire book.
I, personally, thought the last few chapters were drawn out a little long, but otherwise it was well written. The story and the twist provided a great deal of discussion as we deconstructed the novel in class. Specifically, we were able to discuss an unreliable narrator, heavy use of flashbacks, extremely heavy use of metaphor, and foreshadowing as shown by the many not-so-hidden hints the author sprinkled through the story.
I had my students make predictions every day at the end of our listening session to see what they thought was going to end up happening. It was very interesting to see how their guesses developed and what information they used to generate their idea.
Outside of class it would have been a fun, quick read even though I figured out the twist pretty early.