I am preparing for a PCT or CDT thru hike in 2027 and am trying to get my base weight below 8lbs. A general rule I have found is that when hardcore, big miles, ultralight people do things a different way than I am, their way is better. It seems that most experienced people usually go for closed foot box quilts - I have been using a convertible katabatic flex 22 wide. I have been looking at a timmermade serpentes 20 degree with a false bottom (assuming I'm lucky enough to be able to order one) since it's the lightest true 20 degree sleep system out there. However, I am concerned that I will miss the ability to vent the legs. I am a mid twenties man that runs hot, and my legs are usually the first thing to overheat in a bag or quilt. I often have my katabatic flex open, the foot box closed just at the end, or even zipped up, but with the end uncinched for airflow.…