I have a similar dilemma in Nov when I go to the Mexican volcanoes with Richard P. The coolest place will be the 14k hut at Orizaba. I have a +20 REI Subkilo used in the Sierras and a -30 Marmot Cwm, a real beast. So I need to either get a silk or other liner for the Subkilo, or a 0 bag. I am leaning toward a 0 with a semi-rectangular shape so I will not feel so mummified. Harvey
