Doug PM'ed me with a follow-up Q. I PM'ed back, but wanted to add it to the thread in case others are following the discussion.
The Queticos (that Doug is considering) are not as warm as the Arctic model I use. And, if anything, my feet run warm. So the Quetico, for cold feet in the teens and 20's sounds good. There's a lot of leather on those Queticos (hence the higher price?) which looks great (good footwear for a RenFair or SCA event). They suggest, and we did, the spray waterproofing (some variant of ScotchGuard) and while the water does bead up for a long time on the leather, it eventually gets wet. The Tyvek overshoes would avoid that (and add some warmth). Honestly, although I've worn them a lot in some pretty extreme conditions (to -40) and for some long and active days, I haven't done a week of snow camping in them. So I can't speak to moisture build-up over time without using a boot dryer or getting them into a heated house or cabin with its very low humidity. But any boot other than a "mickey-mouse" double vapor barrier arctic boot will struggle with that.
It takes a little getting used to the softer feel of the boots, but I've come to find it an advantage. No break-in period (except letting the insole pack down before trimming anything), and compared to my other -20 to -40 boots, these feel like bunny slippers - big, tall, very warm bunny slippers - but soft and flexible in that way.
A thought on snowshoeing in them: probably better to have wider straps or a newer style heel cup with the wide ski-style buckle around the ankles to spread the load. Shoelace-thickness straps would bite into the mukluks more than most winter boots.
I've got my great-uncle's gold watch and neck ties from the 1930's. A 55-year-old friend is still wearing his father's belt. My Stegers could be one item of clothing I pass down through the generations.
In response to wiiawiwb: What the Stegers do, they do well. But they aren't as versatile as a more rigid boot if you might use crampons, need to kick steps into a snow slope, or need the bite of a hard, lug sole on an wind-blown, sloped icy crust. If you only have one pair of boots for extreme cold and/or if you are on a budget, I'd look on Sierra Trading Post for Kamik, Khombu, Columbia or the classic Sorel models for $90-$150 (after discount).