I don't know, if his ego is as big as it sounds, he may be more inclined to be a tuff guy in a situation where someone is trying to take him down a notch or two. The main reason that I am suggesting that you address this in a non-confrontational manner is because of the potential for violent retribution. I mean you guys are riding on the road. Is this guy such a narcissist that he might attempt to run over your group in his Mercedes?