Depending you what type of backpacking you are considering? Pic a light weight down sleeping bag and pic up a Bivvy Sac which is water proof to keep your sleeping bag dry I'd you go the down route. Personally we went with a bit heavier Northface synthic Tundra bag that if it gets wet it will still keep you warm and it doesn't do nothing when wet like a down bag. Just giving you some thoughts to consider? don't forget a quality stove something like a jet boil and a titanium
Pot?. If your going to cold weather backpack pick up some insulated sleeves to put your backpack food in after you put in the boiling water. Keeps your food much warmer and if you hunt hard try going 2 meal size for one person. Reward yourself for that long walk and hard day in the mountains......we picked up our insulated food sleeves at REI.
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