Most of us on the fourms use down. But the cheeper under quilts use synthetic insulation like insultex and climashield. APEX Climashield packs better and gives more insulation per oz synthetic wise but down beats them all. Down is like bacon transformed into goose feathers.
Bacon and Camping makes me happy.
"When life gives you lemons throw them back"
I camp in bear country and I am a bear Burrito.