Down vs polyester fill for clothing

I see a lot of the merits of synthetic centered on getting wet and losing loft. I see the difference centered on comfort. For me:

–Synth clothing heats up fast and stays that way (really hot, requiring venting). The downside (no pun) is it fails relatively quickly when the temp drops below its "limit."

–Down clothing heats up slowly and adjusts (seemingly) to balance exterior temp with interior temp. And when the temp drops, they fail much more slowly. This yields a wider comfort range with down.

I pretty much know at what temp my synthetic stuff will fail (Primaloft @ 35F, and PolarGuard 3D @ 25, varies by layering), but down is still a (wonderful) mystery (8F once).

I suppose that relying too much on the comfort range of down could lead to unexpected lost of loft (a sudden steep section of trail and I don't remove layers in time, the down gets somewhat saturated with condensed vapor). This hasn't happened, but maybe over several days it might.

But even in summer, I take down (Montbell UL down inner jacket, or Montbell UL down vest). Hasn't failed me yet, YMMV.

IF I know that my insulation layer will ONLY be used as camp clothing and to sleep in, I take down. Even if I am a sweaty pig when I reach camp, I take off all my shirts, put on a 4oz T-shirt and throw on a down jacket. Easy enough to keep dry. Since you use a synthetic bag, any moisture in the down garment will likely be gone by morning if you sleep in it.

However, I usually take a synthetic jacket simply because I MAY need to wear it moving. Last week I was on the 3rd pitch of an easy climb, but the sun just went down because my partner was new an not accustomed to exposure (ok, we were late getting to the cliff too). It got cold with a picth left to go. My Patagonia Micro-puff was perfect to both climb in and rap in, even though I had a 20 pound pack so I was sweating a bit (easy climb, but I suck). A down jacket would have also gotten in the way of the climbing.
I remember a time backpacking when it rained 4 days straight and my skinny self could not stop shivering. I could hike in my primaloft jacket and keep warm. Would not want down there either.
So, for me, down is great for non-active moments, but I only take it on predictable trips where I know I can use it solely for those times. Still, I LOVE the look of a puffy down item- warms me up just at the sight.

Dale,

I don't really see the point in sitting still in camp, next to a wonderfully warm sleepingbag in a down jacket. Why not build camp and directly go into your warm SB??? Could save you the down/synth. jacket.

I only take a downjacket for winter hiking (nothing serious btw: good trail, populated area's really close buy, no mountains, maybe a tiny bit of snow) where i know i'll be fine in a base layer and two fleece jackets while hiking, but where i'll cool off too much while having lunch.

Eins