In a fixed blade its got to be my CS SRK (one of their seconds) which I have literally beaten through things. Another fixed blade beater is my Mora2000, but while I don't care what happens to it, its a little light for really abusive chores.
In a folder, it would have to be my CRKT Mirage with wharncliff blade. Can't pry with it, but I have cut roofing paper and carpet with it.
As for the Benza, I'm not really afraid of doing anything particularly to it, though I note I didn't take it along when I <i>knew</i> I was going to be cutting roofing paper and carpet. But while I don't mind using it hard, I do fear loosing it