Tried out my Katabatic Chisos w/ 2oz overfill to about 20* recently. I was wearing my Rab Microlight Alpine jacket, synthetic tee, midweight long johns, two pairs of SmartWool socks. I was a little less than comfortable and my feet never warmed up. Also had altitude sickness. I was sleeping in the back of my Jeep though with the windows slightly open. The setup was a little awkward and had a few drafts since I was was using the tuck method. Looking to add down booties and pants eventually.
If I was going to be in my Moment, would've switched to a longsleeve merino shirt, add a balaclava, and cinch the cord attachment system tight.