I've based my D&D on Swords&Wizardry White Box with some B/X, LotFP and C&T thrown in and it has worked out really well. S&W is my favorite retro-clone.
I'm starting a new campaign next Saturday and I have 5 enthusiastic players lined up. As far as D&D goes, they've mostly played 3rd edition, but they seem to be okay with the idea of the first few levels being survival horror.
I've been selling it by comparing it to Nethack or other such roguelikes or harcore Diablo II. . .