I'm mining x11 dash at suprnova but i heard
https://www2.coinmine.pl/ was better for dcr and maybe dash. MUE looked the most profitable last time i checked
Keep in mind that coinmine has a 1% fee and there is no fee for suprnova which means in our case suprnova has a 3MH/s advantage over coinmine so when you are mining at 300MH/s you are only getting paid for 297.