You should keep in mind, that Penumbra was Frictional Games first real game. It is clear, that the physic and settings are not as good as Amnesia. And both are different games with different settings and engine.
But it is o.k, when Penumbra wasn't like you expected. Depends on the person, who played the game. IMO Penumbra was really scary, especially Black Plague. Don't know why. The atmosphere of an abandoned mine full of monsters should been scarier, than just an complex called Shelter. But I don't care. I had my shock effects in the game!
But Overture has a heavy atmosphere killer: The Fight System.
(Bam Bam Baaaam!)
Way to easy to kill the dogs, don't you think?
But NOW you have the opportunity to create an own Penumbra in Amnesia using the Editors 
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