when you buy a high end saltwater fly reel, you are paying the bucks to insure that the drag starts smoothly and without hesitation. these drags, for big trophy sized fish (that ain't salmon), are commonly set from 2.5#s to 4.5#s. i suggest you pull out a digital fish scale and see what that feels like straight off the reel. the interesting question is what drag setting do you have to have to avoid creep on a downrigger, humm, have to measure that next time out, or one of you can post the results.
so can a saltwater fly reel handle salmon??? easily. but i spent 90bucks and bought a shimano 2000st, big and ugly, 'cause its going to get abused.