As far as just giving him the loot and hoping for the best.... why?

Someone runs up to you, threatens to kill you by shoving a shotgun in your face, and you're going to take his or her word that they won't hurt you if you do what they ask? No thank you.

They've already shown to have bad judgement, shown that they are not people you can trust, and that they already have the intent or at least willingness to end your life; Why in the world would you enter into a verbal contract with them?

People need to get over this thought that "they just want my wallet." No, they want to end your life. By pointing that gun at you they've already shown the intent to end your life, so you aren't fighting for your wallet -- you're fighting for your life.