I'd go with the Gigabyte GHz edition, because is has 3 fans, technically it cools better than the ACX cooler from EVGA. The K|NGP|N edition is not worth it, unless you're going to do some extreme overclocking than go for it. Not much to say about the Classified edition from EVGA, that card is just a straight up beast, and a good looking card too. Out of the box the K|NGP|N has the best out of the box performance, but it's not worth it. If you can a afford the K|NGP|N, than why not?
I saw the Gigabyte GHz edition has a higher clock speed WTF?!