I currently have an SLD Trail Winder Asym good to 40 degrees. I love this thing. Took me one night to dial it in and it is perfect for me. I have primarily hung in spring and fall. Now due to being cooped up too much I plan on doing some winter camping this year. I will be in the market for an UQ in the 15-20 degree range. My question / concern is as follows: I can get a 20 degree SLD TWinder but I am concerned about the areas that do not have any insulation with the asym design. Could cold winds or cold in general come thru these areas not insulated and have a negative effect on UQ performance? I would certainly consider a full length down UQ if that was a problem. Also I am a side sleeper so I may not always be as diagonal as perhaps I would be on the back. Maybe I'm just over reacting and SLD thought this issue through in the process but any thoughts you folks have will be greatly appreciated. As a senior, while I can afford the expense of a new UQ, I sure as heck can't afford the expense of one that doesn't keep me warm and toasty. Any thoughts, help etc. will be greatly appreciated.