I can't say From a Buick 8 was one of the best S King books i have read, but I didn't exactly hate it either. There isn't much of a plot, just a collection of incidents that have taken place around the existence of this car, that isn't a car. I felt I wanted to know more about the car and where it came from, but then again so did the characters in the story, and I suppose the mystery of it's existence is what this book is all about. At the end of the day, I guess, some things just remain mysteries.
However, the characters are all very much alive on the pages and I thoroughly enjoyed reading them. I am just not too keen on the monsters myself, but that doesn't mean others won't like this book.