For anything other than splash protection I prefer a neoprene deck skirt. The don't seem to be any more steamy than the supposed 'breathable' ones but they stay on much better. The ones with a grippy rubber edge hold onto plastic boats better than the nylon faced neoprene. Just make sure you can remove it with ONE hand. A nylon body tube with velcro combined with a neoprene deck like the Seals Extremetour or Snapdragon Glaciertrek is a little cooler than all neoprene but not as good a seal.