Nice pack. I never thought about material. Wrinkle resistant and fast drying is a real benefit. Underwear is good to wear until you start smelling your chestnuts roasting over an open fire or you notice you got an itch that you just shouldn't be scratching in public. :) I'm a firm believer in the roll the clothes method. Amazing how much room that saves. I need to get a bag like that. Nothing better than only having a carry on. Those leafs are really cool and I'm going to look into getting those. You better start getting some amazon affiliate links. :)