Considering that they're impossible to find in stock, i'd say any gtx 970 is the best gtx 970 right now lol.
Joking aside, the asus strix is good if you don't plan to overclock a lot and want a quiet PC.
The MSI is a better choice for higher clocks with decent cooling without breaking the bank.
The gigabyte has the best (also loudest) cooler so should hit the highest clocks.
Everything i've read says stay away from EVGA for the time being, although i bet that the acx 2.0 cooler corrects any issues people were having.