I don't know most winter campers so I have no idea what they need. My winter camping has been in Yosemiite in about the same place on several trips.

One trip it snowed pretty hard, one trip it snowed and rained and another trip, the sky was clear the whole time, day and night.

I suppose I could have gotten along under a tarp on all three trips, but on the rainy trip, I had a three season tent with no vestibule that that just wasn't a good experience. A tarp would probably have been even more miserable.

However, on the snowy trip, one of the people I was with had a tarp of some sort and he seemed to get along fine. On that trip, Jim Shaw and I were in his TNF Mountain tent and that worked for me because I was sick most of the time and in no mood to be out in the weather.

To me, shelter choices come down to comfort and safety. Everything else is a function of those two points. I drag (literally, on my sled) a big five pole, two vestibule double skin freestanding winter tent for just me because I like comfort and I like safety. Could I get along with less? Probably, but I don't have to and don't want to.
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