I consider this to be King's best literary work. I also consider it to be one of the best pieces of literature in the 20th C. It has nearly all literary motifs, and heavy in symbolism. A good read, and a good study in lit!
My first Stephen King read when I was 13 or 14. It is still my favorite out of his impressive bibliography. I remember carrying my beat up paperback edition just like this one with me everywhere I went.