This is my third insulated jacket. I have a lightweight Primaloft (Mountain Hardwear Compressor) and a lightweight down puffy (OR Virtuoso). I wanted something to fill the void in between the two. A jacket that was WARM but also not overly bulky utilizing synthetic insulation. The Patagonia DAS Parka fit the bill. It's super warm (with 170G of Primaloft versus the 100G of most jackets), well made, and still very packable. It is super comfortable on those cold days. Just beware that this is a belay jacket cut large in the body so you can wear it over many layers. I wear a size Large in Patagonia fleeces and shells and they fit very close, but this jacket in a size Large has way more room and is on the baggy side. I tried on the Patagonia Micropuff hoody for comparison at the Patagonia store, and it has a closer traditional fit, compared to this jacket. The Micropuff only has 100G of Primaloft though.