You might be surprized how much, just a top quality sleeping bag, does for cold weather camping. Maybe it's only psycological or something, but for me, knowing I can just climb in it and get cozy warm anytime I want, helps me to endure the cold and wind before bedtime. And waking up snug, warm and refreshed in the a.m. keeps it tolerable while getting dressed and starting up the stove and/or campfire for another day. And the secret to staying warm in the bag is: the less you have on - the warmer you will be. Your body heat is reflected back to you by the bag and traps that warm air pocket where it does the most good - next to your skin. The initial shock of getting into the "cold" bag will quickly dissipate to comfort provided your bed is dry and sufficiently insulated from the ground or other heat sucking sleeping surface. In 5 yrs of RTT camping, I've not used any heat source other than body heat in my tent. Good quality tent fabric - also helps. I'm surprized at the difference in ambient outside & inside temps - even with venting to keep the moisture under control. My tent is a CVT Mt. Baker hard shell. I know what it's like to shiver all night and start the day under those conditions. Miserable only starts to describe it.
