Up here in the cold north (but not yet the frozen tundra), as long as I am moving I wear soft shell pants, a woven nylon zip T neck that blocks some wind, and a wool hat. If the temp is below about 15 F plus a wind chill then I need to add capilene mid weight top and bottoms and more wind block up top. Stopping, now that is a different matter. 200 level fleece, North Face down jacket, shells top and pants, and a bomber hat will keep me warm down below 0 F as long as I don't just sit completely still. Below -15 F, well just climb in the sleeping bag and stay there. It all depends on what your version of cold is. Phat is probably laughing right now at I call cold <img src="/forums/images/graemlins/wink.gif" alt="" /> I would definately go with the down jacket if you will be sitting still when using it. You can always unzip, but can't add sleeves to a vest.