Amen to that. Everyone thinks that their uberoverclocked 570s are a godsend. Little do they know that almost every 580 can hit at least 900MHz where no other single GPU card can touch it.
Get a pair that can do 935MHz like mine and there isn't anything that can touch your setup. Games will run away whimpering with their tails between their legs once the 580s have had their way.
Needless to say these are very decent cards. I saw the review of the SoC 580 and was thoroughly impressed with what the review stated and if I were a non-reference kind of guy I probably would have gotten them.