I see a **** ton of people using ulrltralight compressed synthetic super magic tactical sleeping bags. It seems everyone has fprgot about the warmest and most versitile bedding system ever devised, the bedroll. Two woolnblankets and a canvas tarp. Light easy to carry and waterproof ( the wool blankets are carried rolled up inside the canvas tarp) thos system rivals the warmth of the priciest sleeping bag out there. When laid out and folded up correctly youll never be cold or wet again...not to mention that wool retains 80% of its insulative properties when wet. And the canvas tarp and blankets can be used for damn near anything, shelter, bedding, an improvised stretcher, wool fluff as tinder, cut into bandages. Look to the old backwoodsmen, they know their stuff