It's a predictable horror story no doubt about it and the whole ghost story isn't really fleshed out, but it is quite a bit scary, in fact I'd say more so than any of the recent bigger horror movies.
It can get a bit boring at times as certain scenes are dragged out and there is literally nothing happening, but the ghost is creepy as hell, the music is eerie and creepy, the whole color of the movie is bleak and just creepy, it really adds to a gloom and doom atmosphere.
Again if you are coming to a horror film to be fully entertained, this is not for you, if you are coming for a great fleshed out story, this ain't it, if you are coming for a scary experience it offers good amount of it. Nothing special, but more scares than most of the recent big horror movies.
I've watched a lot of horror movies, in terms of fun and entertainment this is probably a 3 out of 10, but in terms of scares and creepiness it a good 7 out of 10. Watch it alone in a dark room if you want some good scares.