Rab Mythic G - Down Jacket

Over the last few years we have slowly been upgrading our hiking gear. One item that has been on my radar for an upgrade is a down jacket. I wanted something that really packs a punch at a low weight. After much research I stuck with probabaly my favourite hiking and our door brand, Rab. The Rab Mythic G has become the down jacket of choice for us on our recent hikes. It is a truly ultralight, super warm down jacket that ticks all the boxes for us. We have used it on cool shoulder season hikes in the UK, traverses of Iceland and a freezing weekend in the Polish winter. We have been putting this down through its paces for over a year now and we are very impressed. Rab says this jacket is primarily aimed at climbers, mountaineers and skiers. However, the weight and warmth makes it perfect for those who are weight conscious but want to stay warm at camp.

Specification

Claimed Weight (M): 277g

Fit: Regular

Insulation: 1000fp European Goose Down

Amount of Down: 127g

Main Fabric: 7D Atmon Nylon Ripstop + DWR

Fabric Lining: 7D Ripstop Nylon + Thermic Ionic Lining Technology (TILT)

Hooded/Unhooded: Hooded

Price: £460 RRP

First Impressions

The Rab Mythic G is a jacket that truly lives up to Rab’s reputation for reliable and dependable build quality. Every stitch is perfectly placed, and the craftsmanship is evident in every detail. This is a jacket that has clearly been thoughtfully designed and made. The materials are impressive, with a soft yet delicate feel thanks to the 7D ripstop nylon. One of my initial concerns was whether the TILT lining would feel sweaty against the skin, but it doesn’t. It’s surprisingly comfortable. The fit is excellent, with well designed sleeves, pockets, and hood that stay fitted and help to trap in warm air. The Mythic G absolutely feels like a premium product, which it most certainly needs to be at this price point.

Warmth and Insulation

A down jacket’s primary role, whether you’re hiking or at camp, is to act as an insulating layer, keeping you warm even in the coldest evenings. The Rab Mythic G excels in this department. I’ve tested it at camp well below freezing, paired with just a thin mid-layer and shorts, and it has kept me comfortably warm. Realistically, it’s comfortable down to -5°C, and possibly lower depending on how warm you normally run. Below this, I began to feel a slight chill, but it was still manageable enough to sit around at camp without issue.

This jacket is designed primarily for static use, camp breaks or cold snack stops. When active, I found myself getting far too warm very quickly, and sweating can become an issue with down insulation. The TILT lining is theoretically a great idea. It reflects your body heat back at you, much like an emergency blanket, while leaving gaps in key breathable areas, such as the armpits. It’s hard to say definitively whether it works as intended, but given Rab’s reputation for reliability, I’m inclined to trust it. When you put it on, it feels like wrapping yourself in a warm blanket, and it genuinely keeps you warm even in the coldest evenings.

Compared to other jackets I’ve owned or tested, the Mythic G’s warmth is unmatched.The Mountain Hardwear Ghost Whisperer, for example, although significantly cheaper and 22g lighter, is no comparison in terms of warmth. The Mythic G is in a league of its own.

Weight and Packability

The Rab Mythic G comes with a small stuff sack, and it’s impressively compact. The jacket packs down small enough to fit comfortably in the palm of your hands. Personally, I don’t use the stuff sack. Instead, I pack the jacket directly into the bottom of my bag with my quilt. It completely disappears into your pack, taking up barely any space, however, it is still there for when you need it.

At 277g, it’s hardly noticeable in your pack. For that weight, it’s absolutely worth bringing along, even if you’re not entirely sure you’ll need it. As mentioned earlier, the warmth is exceptional, and with a weight of 277g, its warmth-to-weight ratio is better than most down jackets on the market. On paper it is on par with the Montbell Plasma 1000, but in my opinion, it’s actually far superior. Not significantly heavier, but warmer and a far greater proportion of the weight is attributed to the down insulation compared to the rest of the jacket.

Fit and Comfort

The fit of the Rab Mythic G is nothing short of exceptional. The sleeves stay perfectly in place, even when moving around at camp. They are long enough to not feel as though they are riding up. There’s enough room to move comfortably without feeling loose, so warm air doesn’t escape. The design is sleek and minimalistic and it doesn’t look anywhere near as warm as it actually performs.

The sleeves are nicely long, and the cuff elastic is both comfortable and functional. The hood uses the same soft elastic, which stays put in the wind, creating a cozy bubble of warm air around your head and neck.

As someone who is 6ft 2in and 78kg, I wear a size large, and the jacket fits perfectly. There’s plenty of space to layer up with base layers or mid-layers, but it’s equally comfortable with just a thin base layer underneath. There are no noticeable cold spots and the jacket feels warm all over, thanks to its excellent fit and high-quality insulation.

Weather Resistance

The Rab Mythic G delivers surprisingly good weather resistance, though it’s worth noting that the lightweight fabric and high quality down come with a trade-off. It’s less resilient in wet or damp conditions. That said, we’ve tested it in Iceland and the UK, places notorious for harsh weather, and it has held up without any issues. Short term, it handles light rain well and doesn’t struggle in humid environments, likely thanks to its DWR (Durable Water Repellent) treatment.

However, I’m extremely careful not to expose it to prolonged wet conditions, as even light rain can begin to penetrate the outer fabric after a few minutes. In snow, it performs exceptionally well. Cold, light snowflakes settle on the jacket without melting, thanks to its excellent insulation, and they’re easily brushed off. I’d still be cautious with heavy, wet snowstorms, as these would seep into the jacket. On the rare occasions I’ve gotten the jacket wet, whether from rain or carelessness at camp, I’ve found it dries out reasonably quickly. Within about an hour of spilling water on it, it was comfortably dry and ready to pack away.

Features and Practicality

As an ultralight down jacket, the Rab Mythic G certainly isn’t packed with features. It includes two large pockets, which sit behind the down, making them incredibly warm. The cuffs feature elastic that runs halfway around, keeping them snug against your wrists, while the same elastic is used on the sides of the hood to ensure a secure fit. There’s no additional adjustment on the hood so correct sizing is important. There is just one adjustment toggle on the bottom hem to keep it tight around your body. This works perfectly well while remaining minimalist.

Durability

Durability is an expected trade off with ultralight gear, and the Rab Mythic G is no exception. The 7D ripstop nylon used in its construction is incredibly delicate. It can rip easily if caught on branches, rocks, or other sharp objects while hiking. The thin material also allows feathers to escape, though this happens very slowly and almost unnoticeably. This is purely a result of the ultralight design and isn’t a functional issue and won’t cause any performance issues. That said, this jacket requires careful handling and proper care, especially on long-distance hikes where it’s exposed to rough terrain. If you treat it with caution, it will serve you well, but it’s not the best choice for environments where snags or abrasions are likely.

Pros

• Exceptional Warmth to Weight Ratio

• Premium Build Quality

• Comfortably Fit

• Great For Static Use

• Minimalist and Functional

• Exceptional Warmth

Cons

• Limited Durability

• Average Weather Resistance

• Limited Adjustments

• Price

Final Verdict

If you’re after a warm, reliable, and well made top-tier down jacket, I firmly believe nothing comes close to the Rab Mythic G. It boasts an unrivalled warmth to weight ratio, packs down to almost nothing, and will keep you warm in the coldest evenings at camp, all while helping you maintain an ultralight pack weight.

However, if you need a jacket for rugged hiking or environments where snags and abrasions are likely, I’d recommend looking elsewhere. This jacket excels in controlled, cold-weather conditions but demands careful handling to preserve its performance.