Hi guys,
I have been lurking for a while now and thought I would make an account! I just got a mining rig, 7 GTX 1070's and am planning to mine ETH and see how it goes for a month. I have been concerned with the mining difficulty and feel like I can always switch to ZEC if ETH's difficulty goes up to a level that is unsustainable. I was thinking about just mining ZEC and buying another rig for ETH but hell it is so hard to get GPU's nowadays.
Check profitability on whattomine or some such - ZEC has been more profitable for 1070 cards most of the last 2-3 months than ETH has been, though it's been close some of that time.