I got one two years ago and returned it, extremely disgusted. (If you insist on buying one, get it from REI!)

(1) I could not get comfortable on the thing. No matter how hard I tried (and I tried for 4 months!), I could not find the sweet spot between having my hip bone on the ground and having the pad too hard.

(2) The horizontal tubes meant that I was forever rolling off the thing.

(3) While the pad is theoretically rated at 32*F, I started getting cold at 40*F. To get it down to the mid 20's F you'll need at least a Thermarest Ridge Rest on top of it, which means that any weight saving has gone out the window.

For a similar price and weight, I now have a custom Climashield insulated (to R5) air pad, mummy style, (60" x 20" x 3.5") pad from KookaBay. 12.8 oz. and $150. The custom insulated pads are not shown on the KookaBay website; you'll have to email Bender, the owner, directly. There's a contact form on the website.