Comparison Review: Trying out the most popular insulation garments this winter

I want to know the cutting edge of insulation that can't be understood by specs alone

One of the most important items for staying comfortable outdoors in the winter is undoubtedly warm clothing. When it comes to layering, choosing "insulation"—the layer between your base layer and outer layer—is crucial. New materials and technologies are constantly evolving, resulting in an incredible number of new products being released every year. While this is certainly exciting, it's also true that there's little information available, making it difficult to choose. So, in this article, our editorial team has chosen some noteworthy insulation garments based on their own unique criteria, comparing them under various conditions, and have come up with our recommendations for insulation garments, taking into account not only the material but also the shape and feel

* Please refer to this article for information on how to choose a middle layer

* Please refer to this article for how to choose insulation (down or synthetic fiber)

About the insulation wear compared this time

The six test items for this time are as follows. The prerequisites for selecting these items and the required performance and functions were considered as follows

• It can be used all year round in the climate of Japan (Honshu), from spring to winter. In other words, it is not a bulky cold weather gear that can only be used in the dead of winter, but a lightweight, compact, and highly functional model
• It is not designed for use on hard snow and rocks such as those found in the Alps during the harsh winter, but it is intended to be usable for skiing, snow hiking, and traversing snowy mountains
• Considering the cold weather protection, I generally choose a jacket with a hood
• Since it won't be worn as an outer layer, windproof and waterproof properties are not essential, but it is preferable
• Excludes items that can only be purchased by personal import from Japan or that cost over 50,000 yen (price-performance ratio is also evaluated)
• We select a wide range of down, synthetic fibers, and hybrids

Comparative test items

• Mountain Hardwear Hooded Ghost Whisperer (List price: ¥39,960)

• Arc'teryx Cerium LT (List price: 48,600 yen)

• Mont-bell EX Light Down Jacket (Reference price: 20,304 yen)

• Patagonia Nano Air Hoody (List price: ¥36,720)

• MONTANE FIREBALL JACKET (Reference price: 22,680 yen)

• Mont-bell UL Thermawrap Parka (Reference price: 11,664 yen)

*Prices are from online stores as of December 2014

Test environment

I basically used each item on actual mountain hikes from December to January and compared them. I also wore them while cycling to test wind resistance, exposed them to rain to check water resistance, and basically wore them so many times, from the house to the city, that I almost forgot I was doing a test. Of course, I washed them according to the specified method and verified their usability

I tried it on in a variety of situations from autumn to winter, both in the mountains and in town

Detailed evaluation using field tests

Heat retention...Arc'teryx Cerium LT

Cerium LT > Ghost Whisperer > EX Light Down > FIREBALL = Nano Air > Thermawrap

Our prediction that the power of down would be noticeable to some extent proved correct, but among them, Cerium LT was the strongest! There are various factors behind this. Before explaining that, let's first review the basic logic behind determining warmth: the warmth of insulation is not determined solely by the quality of the filling. For example, with down, the warmth is determined by the overall combination of factors such as the down's source (duck, goose, etc.), quality (fill power), quantity, and baffle structure. For this reason, to take an extreme example, it is possible that a low-quality down with a large amount of filling (heavy) may be warmer than a thin down that simply has a high fill power

For this reason, simply looking at the specs often doesn't tell you how warm the garment will actually be, but after actually wearing one, the Cerium LT, which looks incredibly fluffy, was clearly superior in terms of its warmth. On the other hand, considering the Ghost Whisperer's weight and compactness, its warmth cannot be overlooked in terms of its overall strength as cold weather gear

Comfort: Arc'teryx Cerium LT, Patagonia Nano Air Hoody

Cerium LT = Nano Air > Ghost Whisperer > FIREBALL > EX Light Down > Thermawrap

By "comfortable" here, I don't mean comfort when you sweat or are exposed to wind and rain (more on that later), but simply comfort and ease of movement. The insulation that was the most comfortable and allowed for the greatest freedom of movement was Cerium LT. First of all, the fluffy padding and smooth nylon feel make you feel as if you're always wrapped in a sleeping bag. It also fits comfortably to your body, and its high mobility, eliminating any unnecessary tension or space when you move, is impressive

Another product that deserves special mention for its comfort is the Nano Air. The comfort and feel is truly new, in a good way. Rather than feeling like down, it feels like wearing an incredibly fine, fluffy gauze, which is a strangely comfortable sensation. It's also extremely stretchy, making it incredibly easy to move around in

Weight: Mont-Bell EX Light Down Jacket

EX Light Down > Ghost Whisperer > Cerium LT = Thermawrap > FIREBALL > Nano Air

When it comes to weight, the lighter the better, but needless to say, it would be counterproductive if the functionality was more poor than necessary. In that sense, the key to this category is the relative evaluation of "this is how light it is while still achieving sufficient quality." In that sense, the EX Light Down is incredibly light (despite the handicap of not having a hood). And yet, it still has a decent amount of heat retention, so you can keep it in your winter backpack without any discomfort. You'll never have to worry about getting cold because you misread the weather

Compressibility: Mont-Bell EX Light Down Jacket

EX Light Down > Thermawrap = Ghost Whisperer > FIREBALL = Cerium LT > Nano Air

Some people may not prioritize compactness when folded because it's not a factor in performance when worn, but as someone who likes lightweight and compact items, it's an element I pay particular attention to. The results are as shown in the photo below, highlighting the compactness of the two Montbell products, which focus on functionality and price. The Ghost Whisperer and Fireball also have ample room in the inner pockets, so they can actually be compressed even more than they appear. Conversely, the Nano Air compresses as tightly as possible, making it appear much bulkier than it looks

From top left: Ghost Whisperer, Cerium LT, EX Light Down; from bottom left: Nano Air (stored in a personal stuff sack), FIREBALL, Thermawrap

Breathability: MONTANE FIREBALL JACKET

FIREBALL > Thermawrap = Nano Air > Cerium LT > EX Light Down > Ghost Whisperer

Patagonia's Nano Air has received very high marks in magazine reviews and other publications, so I had high expectations before the test. However, perhaps my expectations were too high, as the results were slightly different. The Fireball has excellent sweat-wicking capabilities. It also has a good balance of insulation (wind resistance), so you won't feel cold or uncomfortable from sweat, even when going from activity to rest. In contrast, the Nano Air feels slightly more stuffy than the Fireball. I thought about the reason for this, and I think it may be related to a phenomenon that only appears on the surface, where moisture that isn't completely wicked away remains on the surface when you sweat a lot (see photo below)

Although it was only a thin layer, the sweat I had produced remained as droplets between the hard shell and the jacket

Incidentally, among the down jackets, the Cerium LT's Down Composite Mapping technology (which places synthetic fibers in areas prone to moisture accumulation to increase heat retention) was more effective than I expected. I was quite surprised at how comfortable it was, almost as good as synthetic products

Water resistance: Synthetic fibers dominate

FIREBALL = Nano Air = Thermawrap > Cerium LT > Ghost Whisperer = EX Light Down

There are two features we're looking for in this category. One is how well the insulation can be maintained when it absorbs moisture. The other is how well it repels moisture before it absorbs it (water repellency). Regarding the former, it's common knowledge that traditional down is finished once it gets wet, while synthetic fibers barely lose their insulation even when wet. In that sense, I was looking forward to seeing how well the water-repellent "Q Shield Down" incorporated into Ghost Whisperer would perform, but the results showed that it still had a long way to go before it reached the level of synthetic fibers. Regarding the latter, all products had some degree of water repellency (see photo below), but I was a little concerned that Ghost Whisperer and EX Light Down easily let water seep in through the seams. Down is delicate, after all

After one wash, the items were sprayed with mist water for about a minute. From top left: Ghost Whisperer, Cerium LT, EX Light Down; from bottom left: Nano Air, FIREBALL, Thermawrap

Wind resistance: Arc'teryx Cerium LT

Cerium LT > Ghost Whisperer > FIREBALL = EX Light Down = Thermawrap > Nano Air

What caught my eye in the strong wind was the high wind resistance of the down products. I expected that the Cerium LT, with its thick padding, would hold up well in strong winds, but I was surprised to see that the other down products also had similarly high wind protection. On the other hand, the performance differences between the synthetic fiber products were extreme (I think this is due to differences in concept), and the superiority of the FIREBALL stood out in the results

Ease of handling: (As expected) synthetic fiber products win by a landslide

FIREBALL = Thermawrap = Nano Air > Cerium LT = Ghost Whisperer = EX Light Down

Basically, all synthetic fiber products can be easily washed in the washing machine, but down jackets require press washing (and it is recommended to use detergent specifically for down jackets). Washing down jackets is more of a hassle than I thought, and it made me realize that down jackets are not something you should wear while sweating

Durability... pending

Basically, there is no sign of deterioration in any of them at this point, but I would like to give a formal evaluation at a later date after wearing them a bit more

Design: Arc'teryx Cerium LT, Montane Fireball Jacket

Cerium LT > FIREBALL = Ghost Whisperer = Nano Air > Thermawrap = EX Light Down

I apologize for always being so subjective in this section, but as Gearzine, we believe that functional beauty is inherent in design, and we want to honestly evaluate excellent style and rational design. Among these, we particularly want to praise the Cerium LT for its form and baffle (partition) structure, which combines function and design, and the FIREBALL for its minimalist, highly mobile form

Price: Mont-Bell UL Thermawrap Parka

Thermawrap > EX Light Down = FIREBALL > Ghost Whisperer = Nano Air > Cerium LT

The price difference between the cheapest Thermawrap and the top-of-the-line Cerium LT is about ¥40,000! To be honest, I feel bad for Montbell for comparing them so directly. That's how amazing the cost performance of Thermawrap and EX Light Down is

Best Item

For maximum comfort and warmth, choose Arc'teryx Cerium LT

This level of warmth is unbelievable in the lightweight, compact insulation category. Adding this much fluffiness and incorporating synthetic fibers in key areas inevitably requires sacrificing packability, weight, and other features. But Arc'teryx is different. They always create the "most useful product." Rather than sacrificing functionality, they'd rather raise the price and achieve everything. In many ways, this manufacturer is a real pain for users! There are many quagmires in the world, and the outdoor world is no exception, too—the "Arc quagmire." The incredible thing about the Cerium LT is that it delivers the warmth and comfort typically found in midweight or higher jackets, all in such a lightweight, compact size. While it's true that its breathability and water resistance aren't as good as synthetics, the company has managed to bring it within acceptable limits through various ingenious innovations

Cerium LT

Arc'teryx

48,600 yen

275g

The Montane Fireball Jacket is easy to use, lightweight, and safe

In short, this is a real bargain. A literal "best buy." It may not be the best of the items we tried out, but once you try it out on the mountain, you'll be amazed at how well-made it is as cold weather gear for use in the mountains. It's warm enough to be used all year round—not too cold or too hot. It's breathable, so you won't get stuffy even in low temperatures (no need to take it off or put it back on). It's windproof and water-resistant just in case. It packs compactly without a bag, so it's portable. While all of these are desirable qualities of outdoor gear, the fact that it achieves all of these things simultaneously is something anyone who does even a little bit of mountain climbing will appreciate. It's without a doubt my best friend this winter

※I wrote a detailed review of the MONTANE FIREBALL JACKET here

FIREBALL JACKET

MONTANE

28,480 yen

425g

summary

This time, I tried out some of Gearzine's recommended insulation wear under a variety of conditions, comparing them from various angles to determine my own best choice

I would like to add that this is not to say that items other than the two mentioned above are not cool, and that down and synthetic fibers still have their strengths and weaknesses as materials, so it is difficult to say that one is superior to the other in all situations. For this reason, I would be happy if you could use the comparison table to find the best item for you, taking into account the situation in which you will be using it, the features you want to prioritize, your budget, etc

   

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