What's the general differences between a 2-button vs 3-button single-breasted suits, in terms of fit and trendiness? I'm assuming 3-button suits are more classic? Does each style fit a certain body shape better? Also, I think I've read that when wearing a 3-button suit, one should not button the bottom button? What about with a 2-button suit? Do you just button both buttons, or leave the bottom unbuttoned?