I've used a Thermarest regular Prolite 3 for a few years and liked the self inflating and lightness
of the pad, but never really felt comfortable on it. So I bought a Big Agnes Insulated Air Core pad a few
weeks ago and had a chance to try it out last week.

The pad is a a few oz heavier than the Thermarest and takes far longer to inflate; the Thermarest only takes a couple of breaths to inflate after being rolled out and left for a few mins, but the Big Agness take 5 mins of blowing to inflate as it is not "self inflating". However it packs smaller than the Thermarest and its 2.5" tickness vs the 1.5 of the Thernarest makes it far more comfortable. Gone is the soreness in the small of my back. Bottomline is that the extra weight and light headedness after inflation of the Big Agnes is well worth the far more confortable night's sleep I get. I'm a convert to Big Agnes.