Build your self and get better components. The 2600 CPU can't overclocked so the "SERVICE Mild Overclocking, 10-20% Performance Increase" is something that Intel CPU do it himself with Turbo technology.
I7-2600 -> i5-2500K ~allows overclocking and is the best bang for the buck cpu atm
Overclock yourself (easy) ~ plenty of Overclocking guides on this forum and others
Change the Caviar Blue to a caviar black ~ much faster
Also switch out the CM for a Corsair / XFX / Antec / Seasonic unit.
two gtx 560 and a good overclock on an i5 will really take no more than 400-550 watts worse case scenario.
So a unit like Corsair TX / HX 750w / Antec HCG/EA750's / XFX 750s units will work just fine and I trust them a whole lot more than any cooler master PSU. (seasonic is wonderful if you can put them in your budget)