The arguments have been made in other threads. I've run Kool Stop Salmons and in the rain and disc brakes just work much better. Does it matter most of the time? No. But for unexpected decelerations in the rain there is no "waiting" for your rims to dry off. The modulation of my disc brakes is fine.
I'll give you that I sucked hard at setting up my ancient cantis. Discs are much easier to maintain.