I have first lite stuff and love it. When it gets below 10 or so and deep snow I will put the north branch pants on over top. They're actually bibs which I like and are very lightly insulated and highly breathable. It's a great combo for me, I can follow dogs all day and they have big zippers that go all the way across the seat if you really need to dump heat. I'm not in the mountains but often 2-3' of snow. Oh they also have built in gaiters which work great when you're punching snow all day, it packs under it if it's wet but you will not get it up past the gaiters.
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