The Fission SL by Arc'teryx is the most minimalistic jacket in our review. With precious few features, no powder skirt, and a simple collarless hood, the Fission SL is basically an all-around jacket that can be pressed into service for ski resort use.
Big mountain, tiny skier. Lead test editor Jed Porter in the Arc'teryx Macai in Jackson, Wyoming.
Arc'teryx doesn't offer information on the quantity of Thermatek Insulation they put into the Fission SL. However, that is what we at OutdoorGearLab are here for. We gather real world information on the performance of all the products we review. In days and days of testing, through the early, cold weeks of the 2016-2017 ski season, we found the Fission SL to be similar in warmth to the average insulated jackets in our review.
The Editors' Choice Arc'teryx Macai is warmer and accomplishes the insulation with durable and lightweight down insulation. The Top Pick Spyder Leader is also a touch warmer, with similar synthetic insulation. The best comparison with the Fission SL is with the Patagonia 3-in-1 Snowshot jacket. The Patagonia features two separate jackets that can be zipped together for the warmest configuration. In this warmest arrangement, the Patagonia is similar to the basic set up of the Fission SL.
Arc'teryx's coastal Canada roots breed high end wet weather performance. Arc'teryx works exclusively with Gore fabrics, which have time and again shown to protect extremely well against wet and wind. The fabric and construction of the Fission SL is bomber, but the overall weather protection suffers with a lack of interior cuffs and a powder skirt. For the absolute best weather protection, check out the Top Pick Norrona Lofoten Gore Tex Pro Shell; the Norrona has a powder skirt and interior wrist cuffs to complement the same Gore fabric. As compared to the insulated jackets, the remarkably soft Helly Hansen Alpha 2.0 keeps all but the wettest weather out with sealed seams, powder skirt, and comfy stretchy wrist gaiters. The Helly Hansen Alpha is more vulnerable to extended rain than the Arc'teryx models, but in normal ski conditions, the Helly Hansen Alpha outperforms in comparison.
The hood of the Fission SL covers all the right parts, without obstructing movement nor view.
The best venting jackets in our test have long pit-zips with no mesh backing. In this regard, the Fission SL is great. No other insulating jacket in our review is similarly equipped. The Patagonia Primo Down comes the closest, with no mesh backing but much shorter openings on the vents. The shell jackets, like the Outdoor Research White Room with its long, mesh-free pit-zips starting on the chest, inherently vent better than any insulating jacket. However, the Fission SL does offer a high performing level of ventilation. The Editors' Choice Arc'teryx Macai has shorter, mesh-backed pit-zips that don't ventilate as well as those on the Fission SL.
This competitor has virtually no ski-specific features. The Top Pick Spyder Leader, for instance, has nearly a full suite of features that the Fission SL has none of.
Fit and Comfort
Arc'teryx tailoring must be something magical. People of all shapes and sizes, through our entire testing history and across multiple clothing categories, find the clothing from this company to fit just right. The Fission SL is light and airy, with no inhibiting binding.
Arc'Teryx hood and collar detailing is, as usual, well-crafted on the Fission SL. This same attention to weatherproofing and wearer comfort earned the Arc'Teryx Macai our Editors' Choice Award.
Aside from bright colors and clean lines, there is little, stylistically to say about the Fission SL. The jacket is the epitome of neutral. One can look at it and legitimately wonder if it were designed for skiing, for climbing, or for just walking around. The Spyder Leader, for instance, screams ski resort, while the Helly Hansen Alpha is a close-fitting town jacket that performs in the mountains.
The smooth lines of the Arc'teryx Fission SL, modeled by our lead editor and IFMGA mountain guide Jed Porter. The careful tailoring and lightweight construction make it one of the most comfortable jackets we tested.
The Arc'teryx Fission is a great all-around jacket that can be used on ski resorts. It is suitable for town life, for ice and alpine climbing, and for backcountry skiing. In the resorts a more purpose-built product will have more robust features and weather protection.
The no-frills design and lightweight insulation of the Fission SL lends itself more to backcountry skiing than to everyday resort use.
No one buys Arc'teryx gear on a budget. It is expensive, high end, and made to last. The value is only realized with extensive use by distinguishing consumers in intense environments.
The Fission SL is an all-around jacket that snuck into our ski jacket review. As such, it makes some compromises but will appeal to a certain segment of this market.
In our Mens Winter Jacket Review we tested the beefier version of this jacket, the Arc'teryx Fission SV.