Arc'Teryx Theta Sk Pant
These bibs are excellent. I have used them on numerous mountaineering and backcountry snowboarding trips. The dual zipper design allows for easy heat venting while hiking and climbing and allows you to put on the bibs without taking the boots off. The built in gaiters have never allowed snow into my boots. They do not limit movement for either technical rock or ice climbing, and they have been able to withstand several chimneys and offwidths without showing almost any wear. The price is steep but they are worth every penny.