I think all the King's Fall primaries need major stat buffs if they are going to compare to all the other raid guns. Every single one needs a slight reload buff (yes I know they are slow because of cocoon, but they are brutally slow. If they had average reload they would be more viable.) Every one also needs a serious stability buff. Buff these two things and you have some awesome raid primaries.
I was using the adept anguish of drysten and the stability was better. I actually enjoyed using it for once. I just switched to my sniper to clean out ads and back to my fully loaded primary. I do enjoy the smite of merain as well. The hand cannon is trash out of all of those