I just returned from a backpacking trip in the high Cascades of Washington in sub-freezing temperatures (mid to low 20's F). I'm typing this on a strange computer so it's not up to my usual standards, but as a result of this trip I have come to very strong conclusions about the NeoAir.

I used the NeoAir with a 1/8" Gossamer Gear Thinlight CC foam pad on top. I FROZE!!! I tried the Thinlight pad both underneath and on top of the NeoAir, and it was warmer with the Thinlight on top--but not enough. In the same conditions last year, with the same sleeping bag and clothing, I was fine with my POE Insulmat Max Thermo (predecessor of the Ether 6).

The NeoAir was a little warmer if I blew it up more than was comfortable, but then it was too firm for my comfort (translation--pressure pains in my hips when on my side) and kept "bucking me off" every time I turned over (which I do a lot). It still was too cold, though. I wouldn't take it out again in below-freezing temps without at least a 3/8" closed cell pad on top (which negates most of the weight savings).

I frankly got so mad at the NeoAir that I am going to go back to carrying the extra 8 oz. of my POE insulated air pad. The extra weight is worth the extra comfort. The NeoAir has never been as comfortable as the POE even in optimal conditions. With the POE I can blow it up halfway and it is perfectly comfortable for me. With the lengthwise tubes and partial inflation, the outer tubes tend to cradle me so I don't fall off it when I turn over, which has always been a problem with the NeoAir. Finally, the larger tubes on the POE pad are effectively thicker,providing more comfort for me and making it harder for my dog to slide onto. The NeoAir with its many small tubes makes a flat enough surface that my dog has a tendency to migrate to it. And of course with the price of the NeoAir, I don't want his claws anywhere near it!

Conclusion: NeoAir not nearly as warm as insulated air pad. For me, not as comfortable (Your Mileage May Vary). Sleeping styles are so individual that you'll have to try it yourself. The one advantage for me is the lighter weight, but I've decided that the weight savings are not worth the reduced comfort. I definitely do not recommend the NeoAir at temps below 35* F.

I haven't decided whether to return the NeoAir to REI, from which I bought it, or to sell it. I will make up my mind when I get home--I can't wait to get rid of it!