Get rid of your sweater, polartec or whatever you are currently using ,replace that layer with the Nano Puff. Warmer and lighter, win-win.
I wanted one pair of sun glasses for long back country trips. I fish a lot and they needed to be polarized. I also climb and do some snow and ice so dark glasses are important. Problem was dark polarized glasses are not good for fishing later in the day, they are too dark. Smith Method was a good solution. The photochromic lenses get pretty dark and they lighten way up for evening fishing.
I would not recommend these for all day in the snow, they don't get that dark. But for up to a couple hours they work fine.
I actually have the Super Methods, they are similar a little larger, better at keeping wind out of your eyes but functionally not much different.