Gtx 1070 single card:
Profit nicehashminer 24hours: $1.89
Profit Signatum sp-mod #3 (0.05btc) 24 hours : $3.06
And how long will it take to pay off that .05BTC? Hint: It's not 45 days.
Even if you could depend on the prices being stable, you are only making an additional $1.17/day, so it would take 120 days to pay off before you make 1 cent of extra profit over mining with NH.
I'm not sure how you're happy with that, especially since the price of SIGT isn't likely to appreciate much with all the extra mining.. now that the open source client is almost at par with sp's client.