I saw that this book was available on Libby to borrow and though it would be an interesting read. This does contain spoilers for some of King's major works.
Throughout the book, there are sections by other contributors that were great to read as it wasn't all one opinion. Some of the contributors were able to clearly communicate and emphasize their points. That said I found some sections repeated ideas and only some of King's works were mentioned. As you read through each section some books show up in multiple areas and it's a little annoying when I know there are other examples they could have pulled from.
I did enjoy this book as a reflection of all the work and mastery that goes into King's works.