Overall, the film is of very high quality and is scary while being respectful i.e. it's not scary by the cheap way of showing you lots and lots of awful things. For example it's not at all like "Audition". It's also well acted, well shot, etc.
The film is somewhat mis-classified as horror, which isn't what it's about. Also, whatever you do, do not read the descriptions and reviews because they consist of nothing but spoilers. Oh, and Hong Kong culture in the film seems entirely obvious and close to ours compared with, say, Japanese.