Saying this base on my experience since I've used both weps before (mythic dags not anymore , using bow now ) . Yes i can agree that dags proc more often than bow but in damage terms , mythic dag proc alone is about x5 your base damage . I have around 7k -7,1kbase damage without dmg lix , mythic dag proc is around 36000+ more or less , + sunken proc is around 70000+ more or less . With these 2 procs you can easily melt boss with just spamming your skills or just use ultimate aim shot( dont remember whats the damage for ultimate aim shot if you hv2 procs ) . For mythic bow , yea proc is kinda bad tbh its very slow compare to dags ive been using bow for awhile now and i do noticed mythic dag procs more than bow during boss fights ( which is very sad lol ) , the proc alone for me damage is not that huge ( 300-400k per shot , 11k base dmg with 25% dmg lix no bd items ) , while mythic bow proc + sunken proc sea blast is 1-1.5m damage ( sorry idk about ultimate aim shot damage while double proc xd ) . And this is all base on my own experience , also I've seen rogues with mythic set 4/4 + dag finish dm boss in 3-4 seconds during proc ( note they are not using ultimate ) , for bow + mythic set I have no idea .