I would go for the Corsair 750TX. I just bought one, and I'm very impressed. The single 12v rail is very stable, and I've always been impressed with Corasair's customer service. You really can't go wrong with either one of those options though. The choice b/t those two psu's is exactly the same dilemma I had a week ago.
"I have found the Iron to be my greatest friend. It never freaks out on me, never runs. Friends may come and go. But two hundred pounds is always two hundred pounds."
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