The 4 piece of the new DH set sucks ass. Who cares about damage mitigation when that set will give perma SS anyway.
M6 still da king.
Based on the wording I took it to mean that you would only get the damage boost for the current amount of disc you have, not the total, so to maximize damage you would always need to shoot when you are at max disc, if you are spamming smoke screen (even if it is refilling completely after a few multishots) it seems like you are leaving a lot of damage on the table. But /shrug I dunno.
Either way though, yeah, M6 is still going to be the best until they nerf it, it's just too good.