I don't mind cum on me, the only thing that bothers me is that if I have cum in my eye, I have to feel my way to the bathroom to get rid of it.
And if it gets in my hair, I have to wash my hair, and I don't like doing that too often (dries hair, and I've got such a thick hair it takes forever to dry.) Of course there are days when none of this matters, so shoot away.