Well, I'm learning....2 layers of reflectix glued together and cut to fit the bottom of the NX 150 with a poncho liner on top of that all slipped into a fleece sleeping bag liner. I slept on it and got pretty warm at about 47* and just a fleece throw on my feet and jeans and a tee shirt inside the storm shield of the NX. I had a wool blanket at the ready but the temp inside the hammock was such that I would have been sweating if I had used the blanket.

Everything stayed put pretty well thru the night and I was fine until 0500 when an owl started blasting away for a mate whooooo soon answered some distance away.

One major flaw at this point...the reflectix gives off the "bag of potato chips" sound every time I moved around which became rather annoying quickly. The reflectix conformed to the shape of the bottom pretty well but needs to be trimmed a bit to make it fit better. I'm hoping I can glue some fleece to the top of the reflectix to mitigate the chrinkeling somewhat and I'm going to trim the sides down to 36" from 40" and see if that helps with the bending to conform with the curved bottom. 40" covers the entire bottom and sides of the NX-150.

Overall, I had <10kt wind and it was pretty warm inside there and I suspect it would be comfortable down into the 30's without any further insulation and just Merino wool base layer to sleep in. Primaloft pants and jacket with wool socks might take it into the 20's or below but I won't have any of those temps to test until next winter. So far I think I may leave out the wool blanket layer but it would add some additional warmth so we'll see how it goes. If I do it would probably be velcroed to the reflectix so it can be removed to be cleaned as necessary.

There is pretty significant bulk to the whole thing so it is not meant for back packing but I think for vehicle based hanging it should work just fine. Cost so far is just the $50 for the roll of 48" x 25' of reflectix since I had the rest laying about.