The voice over is rubbish but the gameplay is awesome and not just Amnesia with different rooms. You are a patient inside a mental institution with no memory of how you got there. A familiar premise but the scares and thrills make up for that. I've squealed like a little girl a few times during the game and that's a tall order.
Despite the "mostly story-telling" tagline, you will be "mostly puzzle-solving" but the game positively drips atmosphere so I will excuse it for the thrills I get in exchange. When even the Frictional developers are excited about the mod, it has to be good.