nano puff or ultralight jacket

I have owned a Nano Puff and I own the down sweater which has a bit more insulation. The down sweater is warmer so I would guess the ultralight down jacket is of similar warmth as the Nano Puff.

The remainder of this post is beyond your question. Feel free to ignore :)

My primary complaint about the Nano Puff is that it didn't breath well at all and I always got clammy under it. Not sure how well the ultralight jacket breaths. I have switched to the R2 jacket as a better mid layer because it breathes so exceptionally well. Throw a wind shirt over it and I think it is an excellent versatile piece.

i own both puff and down sweater.My puff is a little snug and the silky interior has a weird feel on my skin-clammy i guess.I havent used it yet- im trying to find its use but i havent figured it out.The down sweater on the other hand is way more comfy to me a little more roomy but fits great-it kind of floats on me whereas the puff seems to cling.I also have an r2 and r1.The nanopuff has a legendary rep so im in the minority.Its really a personal thing i guess.

A chat with Patagonia (compare down sweater, ultra light down jacket, ultra light down shirt, nano puff)

Down sweater and ultra light jacket have the same amount of fill ~86g
Ultra light down shirt ~56g
Down sweater is warmer than the ultra light down jacket, has bigger baffles.
Ultra light down jacket is warmer than the ultra light down shirt and nano puff
The ultra light down shirt should provide about the same warmth as the nano puff

…because in my experience it handles moisture (rain, sweat, and condensation) better.

I don't actually walk in it much, and when I do it's usually under a rain shell. In that case it seems like the inside of my shell might wet out a little, but the nano doesn't get clammy like down, and doesn't lose it's insulation. Once in a while I'll use just the nano for lunch, resting, around camp, and above timber-line; in that case I appreciate not having to be as careful about keeping it dry as with down.

True, down is a better insulator, pound-for-pound and maybe even by volume… In the store. But for stomping around outdoors I'm not sure that's true, and in any event both jackets are so light and compressible that for my purposes the trade-off favors the nano.

Just my 2¢ worth…

the down sweater and nano pullover.

The nano puff is more versatile. I can wear it throughout the day on a cool day. The zipper works as a "thermostat" as you get too warm or sweaty, it really ventilates when fully unzipped. Zip it up to the throat and it stops wind well and warms you up. At night i'll add an r1 or other layer under it to stay comfortably warm.

If I could only bring one insulation layer, however, it would be the down sweater. Warm, cozy, comfortable.

del

I have the Ultralight and I think it's a brilliant piece. One thing to note is that it's cut to be a mid layer. It's a pretty trim/slim fit. Given its weight and compressed volume, it's a very warm and packable mid layer. I now use mine in my WM Alpinlite to extend it's range, doesn't feel bulky or constricting like many jackets do in a sleeping bag. I also use it under a belay parka to extend its range as well. The Ultralight is a perfect jacket for sumer use around camp. So far, it seems very breathable … as down garments do. The DWR is excellent thus far as well.

what was said above … those UL down jackets match up well with an outer synth layer … it offers good moisture resistance and a decent weight … it will of course be heavier and more expensive than a pure down system

but it is more flexible