Goose Down, Polyester Fiber Fill

[soilman]

I recently did a tiny bit of research on insulation materials in clothing and sleeping bags and my conclusion is that the main reason people prefer goose down to polyester fibers is that it is "natural." As far as advantages, I can't seem to find many. For starters, poly fibers are better insulators, pound for pound. Second, poly fibers still insulate even if they are wet; goose down loses much of its insulation ability when wet. 3. Poly is a lot cheaper pound per pound. 4. Poly is non allergenic. Many people are allergic to goose down. 4. Poly lasts longer. It may last 40 years or more. And when it finally does slowy start to break down, it isn't as irritating. Goose down deteriorates rather suddenly into highly irritating powder that escapes the cloth container it is in and is an allergy-causing protein. 5. Goose down needs to be quilted to prevent it from bunching and double-quilted (so that no quilting seams go all the way thru from outside to inside) at that, to maintain its insulated ability. Polyester can be attached in sheet form without quilting. This means it is much cheaper to manufacture the sleeping bag or clothing that it is in, without wasting insulating value, and easier to maintain the strength of the clothing, with less sewing.

Anyone know of any actual advantages to goose down? I am not sure about fire and flame resistance.