There's this "The Hunt" demo which either is awfully done or simply shows the lack of peformance tuning needed for good looking PC games ...
My PC is not that incredible and the game really runs smooth without problem even on the game editor.
It's not that it runs entirely bad. It's fine until you do certain things which will bring things to a crawl. Stonetrip also knows about this and also has said that some things weren't designed that efficiently. Still - some performance drops are quite "outstanding" considering what is shown / done...
BTW: The regular price is 400 $ - every christmas they offer a certain amount of purchases for a reduced price (so whoever wants to buy it might want to wait for such offers I he / she can)...
EDIT:
I mentioned the version 2.0. Here you can look up some of the coming features like DX11 support, custom shaders and much more...
http://www.stonetrip.com/developer/wiki/index.php?title=Release_Info
