The improved ThermoLite 2 version of the AMK bivy is starting to show up, I saw them at REI this afternoon ($33). It advertises 30% stronger than the first version. I may spring for one eventuallhy to compare to the more compact Heatsheet bivy ($11.79 in quantity from RedFlare), but they seem to use the same material so I'm not sure about the cost/benefit. Last November I slept out in the backyard during 40 degree wet weather in the Heatsheet (blue foam pad, typical hiking clothes, hat and gloves) and passed a quite comfy night rain sheltered beneath a beautiful cedar, since lost to the December windstorm. The Heatsheet held up and is refolded and ready for use in my dayhike gear. I bought a bunch of these when they came out and spread them across kits, cars and relatives. They're small enough to carry extras on Scout outings as well for the inevitable cold Tenderfoot...

ThermoLite 2 description at http://www.adventuremedicalkits.com/kit_...kitNO=0140-0223