You might look at Exped DownMat 7. Ned Tibbits seems to like them a lot and I trust his judgment. It's a down-filled air mattress that uses a pump so that moisture from blowing in it doesn't get the down wet. I just got mine so can't fully review it. One thing that I do know is nice is that you can fully inflate it, thereby maximizing the R-value, and it's still pretty comfortable. Most air-filled things get too hard when you blow them all the way up, but the down seems to keep it soft. Fabric appears quite durable. Not cheap, not UL. I think REI now carries at least some versions of it, so you could return it if it doesn't work for you.
