When the other side pops up in my Freepmail queue I tend to persuade them to put their nonsense out where the lurkers can see it. I don't argue for Luddites and they're very unlikely to persuade me at this stage of my education. They needed to catch me younger or to try again when I'm senile.
And I don't worry about getting nasty in freepmail either. I tell them if they don't like it, get out of my freemail queue.