I was sold on the concept of a vest and tried a high end one out back in the day (Gerry down vest). It didn't work for me and from my experience, I don't really comprehend vests. The design really isn't efficient for keeping you warm by itself because the fill power is almost irrelevant compared to the convection losses happening out of the unsealed arm holes. Kind of like having a house insulated to R100 and leaving both the front and back door open. Even a thin sleeve will seal off air convection losses. I expect a shell over a vest would be much more efficient. But now you have an extra garment -- OK if that is your outfit, anyway but not if it is something extra. My thought is that something less lofty and covering more of your body may be equally warm and potentially provide more versatility.

Of course, if someone has "hot arms syndrome", the vest might be ideal. For me, I prefer a more even distribution of warmth rather than have a toasty core and chilly extremities.

I took the vest back and got a "down sweater" with sleeves and was very satisfied. I still have that Gerry down jacket, but it definitely has seen better days. I'm now in the market for a different one having burned off the arm of my North Face down sweater this past May in the Grand Canyon.
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