Havnt read the last 2 pages, but try looking at the Corsair HX520 or 620 range of PSU's. Much better than the one you first picked and will easily do SLI.
Also you dont need a really huge PSU 90% of the time. Even if you get a 700W PSU, the most your computer will probably draw will be about 400 watts unless you add in lots of drives and lights and fans etc.
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