Down vs. synthetic insulation for sleeping hoods and booties?

Why I have been eyeing synth, specifically Apex:

-Breathing into hoody (I'm thinking balaclava here) builds up moisture.
-Sweaty feet of booties builds up moisture.
-Washability of synth a plus for these items (though for the booties for me personally would be less of an issue).
-For the size of the items the weight gain of synth vs down is small (as opposed to weight gain of a whole sleeping bag or belay parka).

Factors might or might not be big or relevant to you of course.
I think EE as well as MLD have very interesting Apex balaclavas at the moment.

While I think that down is the most efficient insulation, I think that synthetics, like Climashield, might be better for small items like hoods and booties because the insulation won't move around or bunch up. This should help avoid cold spots.

I went through a similar decision curve for my Booties/Hood and finally ended up coming down (pun intended) on the side of synthetic. The fact that feet/head would likely be moisture prone is what convinced me. I ended up going with EE gear and it works awesome for me.

I went synthetic on booties many years ago for two reasons:
1) the down shifted around a lot in the booties, leaving cold spots.
2) Slightly less compressibility is a plus sometimes with the synthetic booties, as when inside overbooties.
3) Much easier to wash.
The amount of insulation in a bootie is pretty small, so the weight difference is tiny.

I'm thinking about making a hood for sleeping and I'll go synthetic on that mostly for the washability – hair oils can get a hood dirty pretty quick.

Definitely some good reasons to favor synthetics here, but I would also consider that down wins for compressibility and durability. If you're trying to take a smaller pack in winter and need the space, or if you're taking a neoprene facemask for wind and sleeping anyway, down may be better, though with such small amounts perhaps the space savings are slim. Down should also last a long time without any loss of function, while Apex will lose some warmth after a couple seasons.

I LOVE my GooseFeetGear down socks. Just sayin'