By my calculations ETH-SIA is narrowly more profitable for my 1070 rig.

What have you set the -dcri to in Claymore? I've got mine on 50 and I'm getting 28.5 MH/s for ETH and 475 MH/s for SIA. I tried setting it to 60 but found ETH dropped to about 27 MH/s whilst SIA only went up to 540 MH/s which wasn't really worth it. How have you clocked your 570s?