User Review: Arc'teryx Men's Gamma MX Jacket
I have used my Gamma MX on a very consistent basis over the last three years, and it has been with me rock climbing, ice climbing, backpacking and winter camping. Due to the superb fit and wonderful drape of the fabric, I have also worn the jacket as my "around town" piece, and as a consequence the jacket has seen a good deal of use and wear.
My experiences with the Gamma MX indicate that although the fit and design of this jacket is unparalleled, the choice of fabric restricts the use of the jacket to light exertion activities where rain is unlikely.
From the outset, the jacket failed to breath adequately when hiking uphill with or without a pack in cool weather. Compared to a Gore-Tex hardshell the Powershield is in fact more breathable, but it in no way matches a decent windshirt, and has always left me overheated, even in winter while wearing only a T-shirt baselayer.
The material is highly wind resistant, but its water shedding abilities deteriorate quickly once the factory DWR wears off. Initially, it would repel light rain, but after a year of use, the fabric simply absorbs water and tends to retain moisture much longer than is practical. Once wet, I cannot dry this jacket on a multi-day trip. I have properly washed, recharged and renewed the DWR to no avail. I rarely ice climb with the MX as the sleeves quickly become saturated and cold.
The fabric is very durable, but will pill eventually. The cuff openings are wonderfully low profile and allow gloves to be layered easily, but mine have stretched out so that they no longer provide a decent seal around the wrist.
The fabric stretches and moves better than any other fabric I have encountered. I love to use this jacket to rock climb in cooler weather due to its low profile, great mobility and durability, and wonderfully placed pockets. However, the breathability and moisture issues dictate that for multi-day or adverse weather activities, a different jacket is a better choice.