Salewa Fusion Hybrid -8 review

One of the biggest innovations in outdoor gear recently has been the introduction of various types of treatment to make duck and goose down hydrophobic – water hating – and this has become virtually standard throughout the industry, with more jackets and sleeping bags now using hydrophobic down than not. What Primaloft’s new Down Blend does is take this concept even further, by not only using hydrophobic down, but combining it with their own synthetic insulation to make an even more water-resilient insulation than even treated down is on its own. It seems such an obvious idea too – to combine the best properties of down (warmth-to-weight ratio and packability) with that of synthetic (quicker drying, better retention of heat when wet) to get the best of both worlds. Like all the best ideas, you wonder why no-one has done it before. But does it actually work?

We recently took delivery of two products that feature Primaloft’s Down blend: the Nangpala jacket from Sherpa Adventure Gear (more of which next month) and the Salewa Fusion Hybrid bag we have here. Sleeping bags would seem to be the ideal product to put this filling into (even more so than jackets), since we rely so heavily on our bags to keep us warm, and a sodden down bag in cold conditions is not something I’d wish on my worse enemy… not often, anyway! Even in environments where you’re not expecting much rain, there are plenty of ways for your bag to get wet; whether it’s through tent condensation, spillages, melting ice/snow or even sweating (a fever I had once when camping completely soaked my bag with sweat); so don’t think that this type of product is purely for use in the UK. With that in mind, lets take a closer look at the Salewa Fusion Hybrid -8 and its Primaloft Down Blend filling.

Fusion Hybrid
The Fusion Hybrid -8 weighs in at just under a kilo (950g), and it has a sister bag in the form of the Fusion Hybrid -2 which, interestingly, weighs exactly the same despite its lower warmth rating. The bag comes with a storage sack and a stuff sack, though this isn’t the roll-top type which is becoming more common with bags these days. The bag has traditional box baffles just like a standard down sleeping bag, into which the down/synthetic fill is stuffed, and the shape is what Salewa call ‘Performance Cut’ – essentially a mummy shape with a bit more space around the shoulders. A 3/4-length zip is located on the left underside of the bag, and a neck baffle runs along the front and back inside the hood. The 15-denier outer feels soft to the touch and overall the bag feels very lofty, comparable to good quality all-down bags.

There are no extraneous features on the Fusion Hybrid -8; you simply get in it, zip it up and pull the single cord pull around the neck to keep out drafts. I’m not entirely sure about the logic of locating the zip on the underside of the bag, but one effect of this is that the baffle that runs behind the zip does stay in place as you are invariably lying on it. There’s a wide strip of stiffened material that runs along the entire length of the zip on either side, and this prevents the zip snagging any material. Even when fumbling or zipping up quickly, we had no problems with snagging.
In terms of warmth, the Fusion seems to compare well with down-only bags. We used the bag on several nights where temperatures dropped below zero, but not down to the bag’s -8 Comfort Limit, which is the limit for the bag’s suggested ‘pleasant’ temperature range for men (for women, it goes down to -3).

It’s always difficult to compare directly with bags from other manufacturers, but looking at Salewa’s own range, you can see that the Phantom -7 (with 90% duck down) actually weighs 200g more than the Fusion, despite being slightly less warm on paper. Admittedly this bag uses duck down rather than goose down, but something like Mountain Equipment’s Xero 550, which does goose down and is rated almost the same as the Fusion in terms of warmth, actually weighs 100g more and costs £100 extra. These figures really surprised us, as we had assumed that the weight/warmth performance would sit somewhere in between that of all-down and all-synthetic insulated bags.

Water Baby
What about the bag’s performance around water though, which is clearly one of its main selling points? We conducted a number of tests indoors (as well as using the bag out on the hill) and, although by no means scientific, they did give us a feel for the bag’s performance. Sticking the bag under a shower for a few minutes we found that water initially beaded on the surface of the bag before starting to wet out eventually, as we would expect. After a few minutes, we hung the bag up and waited to see how long it would take to dry out. A couple of hours later, we came back to find it was almost completely dry and had returned to its usual amount of loft.

We decided to go further and get the bag completely wet, to test its powers of recovery. After submerging the lower half of the bag in water for 10 minutes, by which time it was completely soaked through, we hung the Fusion up, with a little ventilation coming from a half-open window nearby. Drying times will alway depends on conditions (e.g. hanging outside in a breeze would be quicker than inside a tent for example) but our test would at least give us a a guide to the bag’s performance. After just a couple of hours the middle of the bag was starting to dry out, though in one or two areas at the foot of the bag where water was accumulating, the down seem to be quite patchy; you couldn’t say that the filling of the bag had ‘collapsed’ though. 24 hours after the bag’s soaking it had completely dried out, with the Down Blend appearing to loft as well as it had previously; this was achieved without resorting to tennis balls and tumble dryers as you might expect when attempting to dry a standard down bag.

Primaloft seem to have pulled off quite a trick with their Down Blend insulation. We had expected the weight and compression characteristic to be somewhere in between a fully down and a fully synthetic product, but its performance seems more in keeping with pure down products in these respects. It performs well when introduced to water too, but how much better it is than the various hydrophobic downs on the market would need more testing to determine. The Fusion bag itself is well-made and simple in design, and offers similar performance to some down-only bags costing considerably more. As far as Primaloft’s Down Blend is concerned, we expect to see a lot more products using it in the coming months!