Are you talking about THIS one? I have heard and read great things about Enermax PSU's. You might look into those. I don't know if they have single rails or if you are specifically looking for a single rail or if you are interested in a multi-rail. I assume you are looking the single rail. Plus the Enermax's have a 20% off promo code at the egg.
http://www.newegg.com/Product/Produc...0&name=Enermax
I would tell you to get the PC Power & Cooling like mine but it went back up to $500 after I paid $400 for mine.