This layering piece has been one of my most used pieces so far this season. Appropriately named to combat the brutal cold Canada got hit with to end the 2013 thanks to a shift in the Polar Vortex, the jacket had no problems keeping me warm.
Thanks to the Primaloft insulation, the jacket provides an incredible amount of warmth in a very thin, light weight package. The thin construction makes this an easy piece to layer under just about anything depending on conditions. So far I have worn it with both hard and soft shells and don't find any issues with bunching underneath. It also functions well as a stand alone piece, with the fabric doing a great job shedding the occasion precip. At the same time though, I did find the fabric gets a bit clammy against the skin if you wear it too long and start to get warm.
When on the skin track, the jacket packs nicely into its little pouch and takes up less space than a Nalgeen bottle in a pack for quick changes when you top out.
The design of the pockets is very well placed both inside and out. The storm flaps on them take a little to get used to navigate around when you make a quick grab for something, but non-issue once you get used to remembering the different configurations and which reversible side is out.
The diamond quilting pattern does a great job keeping the insulation from settling, and a quick shake out of the pack fluffs it up right away. I've noticed a little insulation material making its way through the outer fabric, but nowhere near the extent it happens with down.
In true Trew fashion, the colors do a great job making it pop and the big thumbs up logo attracts attention all on it own. Being reversible isn't a huge selling feature for me, but I can say it has been worn on both sides, just depends which way the sleeves end up after taking it off.
Overall this, or to be honest any Primaloft piece, is a must have piece of layering that anyone active in a cold climate should have.