Are there any STEAM stats on this, like how many people actually finished the game etc?
Nope. No acheesements. Best you could do is looked at played time and just assume anyone who put in 8 or so hours probably finished.
Er, what? There is exactly one segment containing an actual water monster in Amnesia. There are, however, multiple instances of the game suggesting the presence of a water monster afterwards, without there actually being one - which in my opinion was really well done. So, it's like the total opposite of what you said, bro.
Apparently I'm going senile and you're right. I went back and checked a video and what I experienced was playing through the demo (that had the water monster segment) with playing the actual water monster segment in the full game. Only recently started playing again after about the hour I initially put into it so I had conflated the two experiences~
Overall, though, the game doesn't hold my interest for long. I can only play it in 30-45 minute bits. It's not that it's so scary I can't continue it's just... a little too simple. The experience is sort of like watching an episode of a television series. I get past one major part and stop for a while.