PC Gamer is offering a review for Dark Souls: Prepare to Die Edition, currently only available on PC in the form of a rather barebone port, and despite coming away unimpressed with From Software's ability to adapt the game to the PC platform, they're still rather impressed by the title and award it an 89/100.
And it's how much you let GfWL and the game's direct-from-console port affect your experience that determines whether you'll make the trip down those dark stairs. This game isn't buggy, doesn't crash, and loading times are quicker than they were on console, but you won't find the things you should rightfully demand as a PC gamer here: there are few graphical options and the game is locked at 30 frames per second. For a game this good, I don't think that matters.
If you know the trip downstairs will be long, hard, and sometimes uncomfortable, but you want to take it anyway because you know it will reward you like nothing else if that noise downstairs leaves you too curious to climb back into bed and cover your ears then Dark Souls: Prepare to Die Edition is waiting for you at the bottom of the stairs. I suggest you go and investigate.