Bigbruin.com has posted a review on the Mushkin HP-580AP 580W Enhanced Power Supply
A quote from the article:
Mushkin HP-580AP 580W Enhanced Power Supply Review
Finding a modular power supply that can handle a multi-GPU system can be a little tough, but the Mushkin HP-580AP 580W Enhanced Power Supply seems capable of handling just about any of the latest video cards. And with RailFusion, the system can combine the multiple 12V rails into one if it happens to need more than the 20 Amps provided on a single 12V rail.
Mushkin HP-580AP 580W Enhanced Power Supply Review