IMHO and experience,
Mox Nix, 6 of one, half a dozen of the other...
In the systems i've put together in the last 6 months, both have preformed to their spec's and neither have had defects... and it seams to just the luck of the draw which one ya can squese the most OC out of, both have a little OC in em...
That's if ya get em from a reputible source! - like BEWARE of the local computer show ,your on you own there!
I've been goin with Newegg's best sale price and no problems with either lately.