I am such a Klein fan, I was completely prepared to disagree with the other (negative) reviews of this book. Sadly, having now read it, I have to agree.
"Dark Gods" is phenomenal--four amazing novellas, some of the best horror fiction you will read, and without any gratuitous gore. Klein does it purely on writing skill, building suspense and dread with layer after layer of seemingly insignificant details. In this respect, he reminds me of no less than M.R. James: completely different settings and characters, but a similar approach. "The Events at Poroth Farm" is Klein's other classic in this style.
Klein's novel "The Ceremonies" is "Poroth Farm" expanded. It has its good qualities and is well worth reading, but is perhaps a bit bloated and hence occasionally sluggish. I prefer the shorter novella, myself.
Now, as for "Reassuring Tales"....
Well, one or two of the stories were pretty good. But overall, you won't believe this book is by the same author. Klein himself gives the reason for the publication of the book: he needed the money (he even lists some of his bills). Granted, the introduction is tongue in cheek, but it still rings true.
But then, the final story is "The Events at Poroth Farm," which in my humble opinion is a modern classic.
So, to summarize: Two stars for the inclusion of the final story and one star for the rest. Three stars, but from a five-star writer. Disappointing.