470 as far as power goes.
The Zotac GTX470 on Newegg is $235 before a $20 rebate, so $215
Thats a closer call. $15 difference is real close. I think it comes down to Eyefinity vs CUDA. While I love the idea of Eyefinity, I don't have three monitors. CUDA I can use now, either in production apps or games that support PhysX. For $15 I'd probably get the GTX470. (assuming power and heat wasn't an issue.)