I put this vest to the test in Minnesota recently, layering a fleece under the vest and an Arc'teryx Sigma AR jacket over the vest. The Fusion LT Vest is nice and toasty yet, unlike puffy vests, it is compact enough to easily wear a shell over it. Also, the finish is tougher than puffy vests and so would be less likely to snag and tear. In addition, the material used on the outside is rated as windproof up to 100mph winds.

Excellent Arc'teryx quality, as always, in a comfortable and warm vest.

Hello Gearheads! If you've read my reviews U know I live in Helsinki, Finland. We get nasty, damp cold winds off the Gulf of Finland. Arc'Teryx's Fission LT vest is essential when the temperature drops to -15C and below. When the temperatures are closer to 0C, it's perfect with a soft shell like the Gamma MX or Sigma AR. Another bonus is how great it looks either in Azul or Black.

I live on the Ice Coast and ride Sugarloaf, the place to be. This vest is to be worn only in the forties down, unless you’re standing still, drinking beer. It warms up quickly when moving, and stuffs down to coconut size. Dank as all hell. I love it.
Pricey, but it's what you pay for quality, and this ladies, and gentlemen, is pure Canadian quality.

Arc'teryx has achieved a blend of function and form that is outstanding. This vest is really un-encumbering, yet not too loose or floppy. The shell material is wind proof, water resistant and the insulation is superior. It offers protection in very cold conditions; especially when paired with base layer. It is also very light weight.