I couldn't help thinking though that it was just a clone of Half Life. The story is identical except replace "aliens from another dimension" with "demons from hell" and it plays and looks quite similar, only better and so much DARKER. I think the darkness would drive me nuts after a while.
That said, it really is quite horrifying to play and the music and ambient sounds rule.
Not so sure I'll buy it though. The thought of adding playing computer games to the things I do doesn't make my RSI/OOS feel any better.
Maybe when it's $20...