Rab’s new range of waterproof shells are more than just a slight tweak in design. Throughout the years Rab have become common place for use of fabrics such as eVent, Pertex, NeoShell, including a few of their own such as ProFlex which we reviewed last year. What is surprising is this is Rab’s first partnership with Gore-Tex bringing out a range of high-performance clothing. This is a bold but brave move from Rab as previous designs were trusted and a favoured choice amongst many an outdoors person. That’s not to say the use of Gore-Tex is off putting, in fact it’s quite the opposite for our guides. We often found eVent to be a fantastic summer choice but a tad too cold for winter use and have always swayed towards clothing made with Gore-Tex Pro. Typical of Rab’s continuing strive for development what you receive is not just a Rab jacket replaced with Gore-Tex but a new design altogether which stands out noticeably in the newly updated Muztag GTX.

The Muztag GTX has a reputation as a “light but tough” jacket made for faster paced activities. Almost unrecognisable compared to the previous model the Muztag GTX combines both Gore-Tex Pro Waterproof Technology (40D) with Gore-Tex Active panels (30D). The fabrics are distributed amongst high heat and high abrasion areas which Rab describe as a “fully-featured specialist jacket” which offers “ultimate protection without the weight penalty.” We’ve used many pieces of clothing which use both Gore-Tex Pro, and Active, but did find they were best suited to different activities and seasons. Mixing the two together might appear strange but in theory makes perfect sense.

Weighing in at 480 grams in a medium size this can be considered a light jacket especially considering the number of features and fabrics used. It packs down to a reasonable size taking up little space within our packs and we could see the Muztag GTX fitting into a wide range of activities. The colour we received in Dark Sulphur is one of the best-looking jackets we have used. The bright and bold yellow colour certainly stands out, which was important factor for the winter activities in which we primarily used the Muztag GTX.

As with all Gore-Tex clothing there is a bit of ‘wearing-in’ required which frees up the jacket to become more pliable. The mix of panelling makes the Muztag GTX a very easy wearer, especially noticeable even compared to our older, worn in, Gore-Tex Pro jacket. Although built with an active style fit, there is an abundance of adjusters throughout, (which we will go into more detail throughout the review) offering plenty of room to accommodate bulkier winter layering whilst also pulling more streamline when moving fast with a minimal set up.

The arm and back length are generous which was great for our taller guide, with full unrestrictive movement throughout leaving no areas riding up exposing skin. The hood utilises Rab’s own 3-way adjustable helmet compatible tension system, with wired peak, roll down hood tab and wind collar. A hood can often be an area in which many a jacket has a colossal fail. Rab, we are happy to say, have absolutely nailed this one. Plenty of room to accommodate a helmet or winter headwear, whilst still offering unrestrictive movement of the head. Where it comes into its own is when you are on a long leg of a trip, the heavens open up, winds are howling, and you just want to tuck yourself away free to focus on the task at hand. The adjustments take this large hood and pack it down tightly to the head. When paired with extra face protection you can really hide yourself away from the elements, especially great when battling against a typical Scottish blizzard.

The cuffs have what Rab describe as “knuckle protection.” Basically, this is an extra extension of fabric that helps mitigate any water entering the gloves. It appears to do a decent job stopping any unwanted ice and snow entering. The cuffs open wide enough to accommodate large winter gloves and the Velcro fastening providing a secure hold. The elasticated hem draw cord with one hand adjustment system is a tried and tested feature and is quick and easy to use. A little point of detail we like is that the adjusters are easy to press even with a gloved hand, and apart from the rear head adjusters are also tucked away under fabric or sewn within the jacket, out of the way, to prevent snagging or freezing up.

Pocket space is also a factor which many jacket designs can falter on, and again we were pleased with Rab opting for zipped chest pockets that are large, placed high, free from restrictions whilst wearing a harness or rucksack. The Vislon front zipper and hand pockets use the trusted YKK Aquaguard zippers with large plastic moulded loops that can be easy grabbed hold of for opening and closing. An internal securing clip is a great feature which we use to attach our map and compass. This stops any issue that it might slip out of our hand and be blown off into a glen. This was especially important for us this winter as into the late season there was many a day spent walking in high winds and white out conditions. Internal zip and mesh storage pockets make for plenty of space throughout meaning we were never left wishing for extra.

2-way lightweight full length YKK concealed pit zips offer further venting and did work as a great way to dump heat or regulate body warmth whilst on the move. We paired the Muztag GTX for a number of days with the Rab Keon and it was quite apparent that Rab have aimed several products to work in conjunction with each other. The Keon having uninsulated Pertex Quantum Air underarm panels meant that with the pit zippers of the Muztag GTX open, we could generate fantastic airflow whilst still having some protection against snow and rain. Unfortunately, there are a couple of down points to this area. They are quite fiddly to open and close, and we have found with previous jackets with this same feature it is often the first area in which a weakness will show and water will enter. Having used the Muztag GTX for several months it is yet to show many signs of wear and appears to have a solid build, but it will be interesting to see over prolonged use how this area fairs up.

So, the features throughout the Muztag GTX are well designed and cover every aspect we would like to see in a waterproof shell. For much of the use for this review we mostly paired the Muztag GTX with a mid-weight jacket made using Polartec Alpha, and a simple merino base layer. This is the pairing we would usually use when moving on steep ground in the winter and works well to regulate body warmth whilst importantly wicking away moisture. The Muztag GTX didn’t let us down and if anything, only further enhanced this set up. We were initially concerned that the placement of two separate fabrics could create an unbalance but after much use they work together to provide a great stability between protection and breathability. Against constant heavy downpours, battering’s of snow and ice, and heavy-laden winter packs, the Gore-Tex Pro fought hard and always felt reliant and dependable. The back and underarm panels made using the lighter and more flexible Gore-Tex Active providing comfort in what can be regarded as a very good jacket for breathability. If you do start to overheat the option to dump heat by opening everything up even whilst wearing a pack and harness means that little time is wasted, and a build of moisture can be efficiently dealt with.

We have found it so hard to find much we dislike about the Muztag GTX and trust us we have tried. Even the amount of time between re-proofing appears to solid. The test of time may bring up a few issues as with the separate use of fabrics and the underarm zippers we would expect some signs of wear to appear eventually in these areas, but for now this is an absolute belter of a jacket.

Our Verdict

It would be hard to imagine Rab having a tough time in shifting the Muztag GTX. Not only is it a great all-rounder but it's also a very good-looking jacket. Featuring an abundance of well-considered and implemented features offering full protection against the harshest Scottish conditions. The Muztag GTX is not just a great jacket for use in winter, but we believe it has all the qualities for all year use throughout a range of activities. Rab's move to Gore-Tex sure did raise a few eyebrows and so to did their design pairing Gore-Tex Pro and Active on a single jacket. It was a bold move but one that has triumphed for us. It will be interesting to see how this partnership develops and the new products to be introduced in the future.

Trek Scotland is a small family business based in the picturesque village of Tomintoul in the North East region of the Cairngorms National Park. They provide bespoke Mountain Guiding for Single Day Walks and Lightweight Multiday Trekking experiences, including wild camping, in the stunning Cairngorms wilderness and surrounding areas. Whether in the high mountains or lower valleys, their Multiday Treks are equipped with high quality, lightweight camping and trekking gear. They only work with small groups and, whatever your ability, pride themselves on designing your outdoor experience completely to your needs and with professional guidance and expertise. Adventure is waiting...