A lot of people on this forum sleep on pads that reach from hip to shoulder. They use a pack or other padding to insulate their legs and a stuff sack containing extra clothing as a pillow. Having a full-length pad is somewhat of a luxury and you pay for it with it's weight. If you are trying to lighten your pack you should be thinking of ways to minimize the amount of pad you carry consistent with good insulation and a good night's sleep.