I never show. Poker is a game of information and even when you do so by trying to mislead opponents, that in itself is still giving away information that I'd rather keep to myself. When playing someone who hasn't shown his cards the entire game and all of a sudden he reveals a monster, I don't think "oh, he must have great cards all the time", I become suspicious. I just think he's trying to set up a bluff, which is what they usually are doing