Two of my climbing and scrambling friends have been using these in sloppy weather with great success. They work well on days when you are working hard enough to sweat, but the weather conditions are damp. They let the sweat out and keep the rain in. I love that they aren't bulky. I did teach ice ax arrest in them last weekend, and they aren't great submersed in wet snow, but pretty much all my gear gets soaked through on days like that.