Stephen King is an author I left alone for a good few years, but read his 'Under the Dome' just after Christmas, and picked this one off my shelf a couple of weeks ago. It is not his longest novel, but it is one of his best, I think. I like the way he builds character and, and his handling of the growing relationship between Edgar and Wireman was particularly well done. If I have a criticism, it is a tiny one, in that I think he could have developed Jack a tad more.
However, it is a slow paced novel, but that seemed to be entirely in keeping with the themes which he was exploring, the nature of recovery, and the way our minds think and how we interact with other people and also the situations we find ourselves in.
It could be argued that this is derivative, as one of the reviews I read did, but I don't think that is the point. It is not always what you write about, but how you do it, and I feel that King does it better than many other authors about at the moment.
Read, enjoy. I found it worth the time, as I have been glued to the bed until I finished it - always a good sign, ha ha.