This is a ‘bothy bag’ shelter. Enclosed water- and windproof, that you sit in for a break or an emergency. Your body provides the structure. This makes it fast to pull out and use for a break, where you wouldn’t bother with something that needs stakes, poles or guylines. Once inside, especially if it is windy or wet, it is much warmer, and dry, so you can change gear, look at a map, eat a snack etc, without getting gear wet or freezing. So far about the category in general.
I have the ‘4 person’ version, which is very tight for 4 adults. It is, as far as I know the largest lightweight one though.
If you almost always go out with just one other person, the 2 person version shown here will be a bit tighter (less flapping) in the wind.
Props for the ‘stuffsack’ actually being one of the vents, this saves weight and prevents you from losing the stuffsack in the wind.
The picture is inside, with 25mph wind, wet snow and 26F outside, 2 of us in the 4 person version. You can see what conditions where like inherent first pic, yet inside, I could open up my jacket, use my hands without freezing and open my backpack without filling it with snow.