Which GTX 960 GPU?

There's no single "best" card, so maybe you wanna explain to us first what you look for in a card. Like, the one with the highest clock speeds? The quietest card? Also there's small form factor cards and really big ones that don't fit in every case.
 
Sorry for the misunderstanding. What I mean is which of the 3 versions in each set would be fastest:

2GBs
-GTX 960 ACX 2.0+ 2GB
-GTX 960 SC 2GB
-GTX 960 SuperSC ACX 2.0+ 2GB

4GBs
-GTX 960 FTW ACX 2.0+ 4GB
-GTX 960 SC 4GB
-GTX 960 SC ACX 2.0+ 4GB
 
Oh you mean which EVGA card is the best... Nerdrage is correct, those would be the fastest from your list. "FTW" cards are the fastest, as they always have the highest clock speeds out-of-the-box. S(uper)SC has a little lower clock speeds, SC even lower, and the slowest clocked models have no additional name to it. The differences aren't very big though, we're talking about maybe a couple percents.

By the way, "ACX" is just the name of the cooler. All 960 cards have ACX 2.0 coolers, and I believe they're all semi-passive ones (fans only start spinning when the GPU temperature rises above a certain point).