If mining ETH, GTX 1070 gets 31MH/s while 1060 gets 23MH/s. The 3GB 1060 is half the cost of the 1070 while producing 75% the hashrate. Do you not consider the 3GB 1060 a good choice because it will become obsolete due to only 3GB vram? It seems like the next best thing to an RX 570 for mining RIGHT NOW. They can always be sold when the vram becomes too small to mine.
the 1070 is supposed to get 31MH/s? Mine is only getting 25-26MH/s, but I'm also using stock-clocks and Nicehash's default selection for miner.
on a side note: my 1070 purchase was a bit about working through this drought of AMD cards while helping someone upgrade a
non-mining older AMD gaming machine, so sold him my under-performing on eth XFX RX 470 and replaced with the 1070. I'll probably also end up with his HD 7870 and FX-4100 for a tiny bit of expansion. 7870s aren't efficient, but they do still earn more than they cost to run.