The new Claymore Neoscrypt miner is pretty good too - if you increase the power limit you get quite high hashrate, but I prefer to leave the power at stock.... stock Rx 480 8GB does 860 kh/s (can be tweaked higher) and Rx 470/570 does around 740-750 at stock settings. The good old Fury X does 1550-1600 kh/s at stock and 1190 kh/s at -50% power.... I don't have any Vega GPUs, but people report 2000 Kh/s with that new miner.
So, Claymore's Neoscrypt miner is maybe 3% faster than Gateless Gate, before subtracting out the devfee. I use his Ethash miner because it is by far the fastest and most stable, but try to use any miner besides his for the other algos because he's turning into the Bitmain of GPU mining software.
I had previously only tested Claymore's Neoscrypt miner on a pair of personal desktops and got the above results. Today I was setting up a few of my wife's business rigs and I got quite abit higher. The average hashrate across 6 Rx 480 8GB was 950 Kh/s and the average across 18 Rx 470/570 4Gb was 750 Kh/s - these were all at 100% stock settings with now -powlim adjustments and the -a 2 parameter.