Came here from Lost (Sawyer and Ben quoted it) and I found it very interesting.
I liked it at the first reading, but I definitely need a second one to elaborate more thoughts.
The relationship between the two protagonists is moving, especially if you have a soft spot for sibling tropes. 
Plot and writing are very simple, maybe that's why I had a hard time getting a complete picture of the book, it's open to interpretations.