Is there any reason you wouldn't want to just stack pads? That's what I do with two Ridgrests. I'm a sidesleeper who bought a short NeoAir, loved it for the comfort but like, you, wanted something fail-proof for trips in colder weather or longer than 1 night.
2 Ridgerest's stacked =1.25" thickness and an R-Value of ~5.2, which covers you into winter. I have a regular length and a short length, both of which I cut to fit and which now have a weight of 5.57oz(short) and 9.28(regular) for 14.85oz total. In winter I'm also experimenting with using a 3/16" thick 60"x38" mat from Oware as a ground sheet for some added insulation vs a spinnaker, tyvek or silnylon ground sheet. At 5.68oz, the weight penalty is only a couple oz, and I get the benefit of .6 R-Value.
This system isn't as cushy as the NeoAir, but it also won't ever leak and leave me on the ground. I'd guess I find it about 65-70% as comfy as the NeoAir, and, having used REI's 1.5" thick version of a Prolite, about 90% as comfortable as that. Plus, with the Ridgerests, I don't get that cold spot where my hip indents the mat. Also, I've been working on back-sleeping when out, and when I do that, it solves any comfort issues.
Here's a picture of my system.
The short mat is 38" long and 19." wide at the widest. The longer mat is 71" (I'm 5'10") long and 19.5" at its widest. The leg portion is 15" at its widest.