I borrowed a friends Therm-a-Rest NeoAir sleeping pad on my last hike and was presently surprised. I was so surprised that I sent back my current pad and bought this one. The weight and pack-ability are far superior to anything I have ever used. I found it to be very comfortable and the size to weight to price ratio worth it. I look forward to using it on some late fall and winter backpacks this year. With an R-value of 4.9 and 2.5 inch thickness, the sleeping pad provides excellent insulation from the cold ground. The long size weighs in at only 25 ounces and packs up to be about the size of a Nalgene bottle.