Good report Roger, but i'll disagree with you on there not being much difference between the 55" width of the Nunatak, and the 52" (i measure mine more at 51") of the Sawatch. The Sawatch was advertised originaly at 54". If i had known it was so narrow, i wouldn't have bought it.
I'm a side sleeper, and 55" gives me enough tuck. 51"/52" is too narrow, and both sides of the quilt don't touch the ground when i'm on my side, unless i use the cords. I don't use the straps on my Arc Specialist, but need to use the cords on the Sawatch. It just works ok, but i prefer the freedom of more room. I love quilts for their non-restrictiveness, as well as the weight savings. As a side sleeper, i find the Sawatch is more like a restrictive sleeping bag for me.
And yes, that single snap won't stay closed! I'll try to figure out a way of adding another snap, without damaging the thin shell material. I'll maybe get a seamstress to do it, and add a few inches of material to the sides at the same time.
It's a top quality quilt, but too narrow for comfort for this side sleeper.
I'm 5'10", 42" chest, and around 170lbs.
Edit. I've just emailed Aaron to see if he will update my quilt. Apart from the single snap, the elastic edgeing may give a better seal.