Great discussion. I currently use the following: Icebreaker 260 (baselayer); marmot driclime windshirt (midlayer) and arcteyrx stingray (shell). Seems to keep me warm down to 20-25F (could go a bit lower, but the lifts at that temp can be a bit cold). I'm considering a different midlayer, and would appreciate everyone's input. The windshirt keeps me relatively warm, but how does it compare to a synthetic (e.g. arcteyrx atom lt) or a down (e.g. patagonia down sweater)? Also, I find the windshirt to be very poor at breathability - probably my biggest, only complaint with this item. How does the windshirt compare to the synthetics and downs mentioned above?
Thanks in advance.