Comparative reviews wouldn’t be much fun without the occasional oddity to set things alight, and the Plasma truly lights a fire among the down jackets. Whereas most jackets featured are ideal for chilly but dry backpacking weather, this is the only one I would contemplate wearing for a blizzard-whipped winter assault on a coveted Munro.

This is a fully waterproof down jacket, utilising breathable eVent fabric and featuring welded seams to circumvent the problems of damp down. Yet it’s still light: even with robust, polyurethane-coated, water-resistant Riri Aquazips and a detachable, fully insulated hood, the jacket clocks in at an impressively low weight of 576g (size L), less than some non-insulated hardshells designed for similar conditions.

The outer shell is crispier and noisier than, say, the near-ubiquitous Pertex fabrics found in the down jacket world but, let’s face it, you’re not likely to go bird-watching in the Plasma (especially not in the hi-vis yellow sample sent for testing!). Attention to detail is wonderful: drawcord toggles can be (just) operated when wearing gloves; internal drop pockets are perfectly sized for flasks, Nalgene or Sigg bottles and have mesh sides to allow condensation to escape; external hand-warming pockets can be accessed when your pack belt is fastened.

These days I tend to prefer Extra Large sized garments for test but found the Large size supplied fitted well; if anything it was just a tad short. I also prefer insulated garments to be hood-free but, given the conditions this jacket is designed for, I think the detachable hood only increases its versatility.

The Plasma is one of the bulkier jackets featured, even though the eVent outer allows some air to escape when packing it away. But given that it gets around so many problems with using down in our damp nation, that’s a minor niggle. I’m looking forward to getting some more use out of this over winter and I’m not talking about scaling a butter mountain.