I haven't read it yet, but I will be. I just started reading Joe Hill in September, with Heart Shaped Box, now reading Horns. I'm very much looking forward to getting my copy of NOS4A2 to start reading it.
Heart Shaped Box was more of an out and out ghost story.
There is a little more to it than that, but it didn't have the fantasy aspect of NOS4A2.
Also the "this is the good guy/bad guy dynamic" was a bit too simple (in comparison to NOS4A2) in my opinion.
That said, I still enjoyed it and would say it is definitely worth a read if you can find it