One of my students was reading it in class about 5 years ago (scary the similarity in time!), and he recommended it. The book actually made the rounds of the classroom over the course of the school year, with all of the boys and about half the girls reading it. Of course, I made the mistake of reading it right before a field trip, and was paranoid on the entire bus ride out and back.^^

I've read bits of the manga in the bookstore, just because I like the art. But every time I do, I'm reminded why I don't like the adaptation. I agree: it doesn't really work. Maybe that's why Takami stopped work on the manga sequel.