Gents, having skinned my knuckles and sprained my hands, not to mention embedding black dust into my freezing cold digits for a week, I would rather change a pair of pads on disc than a pair of shoes on a drum any day, last time I did shoes I could have killed my father in law for asking me to do it. I don't see corrosion as a problem on discs as it will wear off in seconds if the pads are applied in anger, also, grooving makes no difference, after all, it's not across the direction of rotation is it?