NOS4A2 is one of my favorite books and Joe Hill one of my favorite authors. The first time I read this I felt like I'd read the most fantastical sort of dark fairytale. I couldn't stop thinking about it for days. That being said, the book is somewhat long and does jumps back and forth between Vic's & Manx's storylines; it can be somewhat of a slow burn at times.
If something is being adapted from a book, I always try to read the book first, if I haven't yet, since it's almost always better than any adaptation. I haven't watched any of the episodes yet - I was saving them to watch them all at once at the end (& my husband to finish reading the book). But I knew I wasn't going to be happy when I read the synopsis for the first episode. They've changed so much of the storyline to get it from the book to the screen. Sure, it's the same basic story of Vic against Manx, but everything else, what makes the story the story, is lost. So I don't anticipate I'll be watching it. It's the main reason I get nervous when a book I love gets turned into a tv show or movie.