I had 2 FPS installed on my PC, Far Cry and Doom 3. I only tested Doom 3 as I liked the dark athmosphere, and I also loved the setting in Far Cry on the island. But I didn't even play the first level, it was nice to show my friends in the beginning, but that's all.
Anyway, I was also impressed when I saw Stalker and now Bioshock, but with my X800 GPU, it won't run properly I suppose. And if I'm honest, I don't even care. I really converted from PC gamer to console gamer, which was due to japanese RPG games. And I prefer playing sports and racing games on the console, as it runs perfectly, doesn't need an install, and is perfectly controllable with a gamepad.