This bag is a work of art. The 10D fabric is silky soft on your skin, the hood cinches down to create a nice seal, and the draft collar is stuffed full of luxurious down and adjusts smoothly. The interior fabric is a bright, translucent green and the exterior a svelte, glossy black. The Plasma is neither constrictively narrow, nor is it roomy, striking a nice balance between warmth and spaciousness. The footbox is well constructed, and the full length zipper operates smoothly, providing venting or clean mating with a Helium or Pinnacle. The Plasma comes with an ultralight stuffsack as well as a nice mesh storage bag, with "900 FILL" emblazoned on the bottom in huge, heart-racing numbers. Marmot has cleverly used synthetic insulation in the draft tube to keep it evenly stuffed, and it works quite nicely.
With the stuff sack, the Plasma weighs in at 1lb 8oz on my scale. The EN rating of 32ºF seems accurate, I was cool but comfortable sleeping outside on a 30º night in Joshua Tree NP with a hat, socks, and midweight baselayer.
But is it worth $420?
Depends on who you are I guess. If you absolutely must own the best of everything at all times, this is your bag. Its primo. If you want to get the most for your dollar, however, you can do much better. The Hydrogen, for example, is EN rated 3º warmer, costs $80 less, and only weighs an ounce or two more*. The Hydrogen's warmth rating is achieved without a draft collar and with roomier dimensions, making it far more comfortable. The thicker fabric on the Hydrogen holds in the down better (the Plasma sheds feathers from the seams occasionally) and its horizontal baffles mitigate down shift - a big problem i notice with the Plasma's longer vertical ones.
Overall, the Plasma is a very unique and worthy piece of gear, and I'm glad I bought it, but I wouldn't necessarily recommend it, nor would I tell you it's worth the money.
*according to my scale
- Helpful? (6)