My RX550 with 2GB gives 420...430 h/s on "Gateless Gate" and on "STAK XMR". The key is "threads=2". With its price under $100 and ~75 Watt power, I think it's a good choice now.
Claymore, please, bring back support of "Polaris 12", at least to the degree as of v9.7 !
What's your raw/intensity?
{
"algorithm": "cryptonight",
"rawintensity": "320",
"worksize": "16",
"gpu-threads": "2",
...and, certainly, patched BIOS plus some overclock in WattMan.