I work as a professional ski patroller during the winter and just got home from work on a day where it was darned windy and didm't break +10. I'm wearing 3 layers of fleece and had a down vest under a goretex shell. I don't have much experience with primaloft or promaloft/down, but haven't bought it because I don't see it filling a need. I wear fleece under an outer layer when I hunt and carry a down jacket in my pack as a backup. If I'm so cold I need the down it's unlikely that I'm sweating so the down isn't likely to get wet. I'm also a big far of wool but am old enough to be old school without being a hipster. I hunted a couple of days this fall with a buddy who has is an Alaska Master Guide. When he got cold he pulled out a down piece.
YMMV.
Frank
Fleece midlayers has been my go-to for about the last 10 years. Fleece is very breathable but not as warm at down/primaloft. The issue is hiking with down encapsulated in nylon doesn't breathe real well and I sweat. Hiking into a spot to sit works great with fleece but it isn't warm enough when temps start to dip in the high country. I haven't played with the newer puffy jackets but think hiking is a fleece mid-layer deal and sitting is a puff jacket under the outer shell deal.
I bought a primaloft packable jacket this weekend with 100 grams primaloft encased in some type of non-nylon fabric. Thinking it might solve both isues. We'll see.
