I really enjoyed this. Sometimes Agatha Christie's can get a bit repetitive and are less enjoyable, but this was one of her best - right up there with The murder of Roger Ackroyd. I enjoy the character of Superintendent Battle, and the rest of the characterisation in this was just as good. I particularly liked the fact that any of the characters could have been the murderer. It makes it that much more satisfying a mystery. There were also a fair number of unrelated matters, snippets out of the characters' ordinary lives that helped make the story believable and more satisfying. Particularly as they were given without comment or anything relating them to the later bit they were to do with. At the same time, it still managed to be a quick, light read.
All in all, I'd certainly recommend this to anyone who enjoys a good mystery.