I'm a huge King fan, but I could agree with Nightmares & Dreamscapes. I think when compared to Night Shift (which I LOVE) and Skeleton Crew, its definitely the weakest of the three.

And I was a bit disappointed with the direction he went in the Dark Tower series starting with the fifth book, where he began inserting himself into the story. The first four books are absolute gold, but I was a bit underwhelmed with the last three. Still great reads, mind you, but not up to par with the first four.