I got about an 16 MH/s increase with 6 RX 570 Sapphire Pulse 4 Gb, which is pretty much like having a 7th gpu running along.
Went from 16,5-17 MH/s on SGminer to over 19 Mh/s.

Definitely makes up for the 1% devfee. Thank you so much and please keep optimizing this miner! Finnally we AMD miners get some upgrade to mine SIGT.

Thanks again!