Zotac AMP! Extreme 1070 or Asus Strix R9 Fury?

Hi! I'm between these two to start my first 7 GPU rig, ready to pull the trigger.
Electricity isn't a problem since it's mad cheap in my country, and these two round about the same price.

For either ZEC or ETH, which of these two mines best overall? I will OC and mod to get the highest results possible!

Thanks!