Tim wrote a review of Arc'teryx Nuclei Hooded Insulated Jacket - Men's on January 20, 2014
Familiarity: I've used it several times
Fit: Runs small
The Nuclei is very warm, well, even without taking into account the weight, or lack of it. Packs into a very small bundle, cuffs fit well, though not quite as good as the Atom LT. Sizing, for me, is a bit on the small side, especially across the chest. I was a little surprised at that. I had hoped that it would be a bit of a looser fit than the Atom LT. Especially as I was wanting to use (the Nuclei) as a minimalist belay jacket-however, that is not a deal-breaker, by any means. The best part is the warmth of this thing, flat amazing for the weight. That is enough to earn my respect.