M.R. James writes like an old English scholar; upper class and antiquated. I have been gradually making my way through this collection of stories over the last 18 months and I should probably not have spread them so thinly. I was able to enjoy the stories more when I read a few in quick succession and got used to his style.
Some of the stories were quite chilling such as "The Ash Tree" and "Rats". Others were extremely subtle and complex with multi layered narratives and requiring the reader to make deductions that were not always spelled out. This worked well with stories like "Martin's Close" but was just too obscure (for me) when it came to stories such as "Two Doctors". Other stories mixed in a fair bit of humour such as "Oh whistle, my lad, and I'll come get you".
I definitely think that the stories are best read in the right setting, say a candle lit room at night and would probably benefit from being read aloud by a good story teller.