If my mission was to promote my beliefs over his, YES. I would do what I could to show him the error of his religion/god(s). But I'm not a JW anymore. I'm content to be a Christian who NOW understands that man's salvation is based on the condition of heart rather than some individual notion of doctrinal purity or understanding of the identity of God.
NOW, my approach would be more like the one NAVYTOWN mentioned - turning it in to a learning experience for myself.
NOW, I could part company with the guy without viewing him as buzzard food.