Steve,
My wife and I have used the Therm-A-Rest chair sleeves with our Therm-A-Rest pads for years now on our canoe trips and I love them. We never go without them. You can sit them on the ground with your legs out straight or lean back in them with knees bent like a recliner, sit in them cross legged, or you can rest them on a rock or log so it feels more like a conventional, raised chair.
Like you, I have back trouble (lower back), and I find that sitting on the ground or on logs, etc without back support starts to get uncomfortable after a couple of days, so having something with a backrest is important for me, especially when reading under the tarp in the pouring rain for hours.
I imagine it would serve well in a hot-tent as well, especially if you cut a trench just inside the door where you could dangle your feet.
Here are a few photos of us sitting on them to give you an idea of how they look when in actual use.
http://i1122.photobucket.com/albums/l52 ... 0b6d60.jpghttp://i1122.photobucket.com/albums/l52 ... chair1.jpghttp://i1122.photobucket.com/albums/l52 ... chair2.jpgHope this helps,
- Martin
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