Hello,
Technically,there are no differences in gaming performance in either of those, all has same GTX 970 chip in them, you want the one which is cheaper to you,service is good in your area,looks well with your build.
In my experiance, the ASUS and EVGA been the best in terms of quality and service.
As for RAM, i'd look for 8gb DDR3 of 1600mhz speeds.