The Marmot Plasma 30 is lightweight at a high price. The hood of the Plasma is luxurious and scores major points for comfort. Overall, our testers think this is one of the best bags reviewed, but felt that they couldn't justify paying the extra money for a bag that is pretty limited to summertime mountain activities. For warmer climates, this is an excellent sleeping bag that may span more seasons.
Marmot Plasma 30 Review
Our Analysis and Test Results
A very lightweight and warm bag, the Marmot Plasma 30 is one of our favorites.
In the sub-1.5 pound category of this review, the Marmot Plasma 30 is the warmest and most confidence inspiring sleeping bag we carried. Compared to the Top Pick award winning Sea to Summit Spark Sp II, it has more high quality down insulation, a full draft collar, and a comfortable hood that can be cinched down without suffocating for nights near the bag's comfort limit. We really like the comfort of the trapezoidal footbox that Marmot used on it and found the shape to be quite warm. The Pertex Quantum outer fabric has some wind resistant qualities which are handy for sleeping under starry skies outside of a shelter to break the wind.
The only two backpacking sleeping bags that are lighter than the Marmot Plasma 30 in our review are the Sea to Summit Spark (18 oz.) and the Western Mountaineering HighLite (16.2 oz.). The Plasma has a better insulation-weight-to-material-weight ratio than the Sea to Summit, but not quite as low as the WM HighLite. A quick way to shave a little bit of weight from this bag would be to shorten the zipper to a ½ length or ⅓ length like the others. Considering that it also has a full length draft tube along the zipper and a functional draft collar, the extra weight is actually quite functional on the Plasma 30.
The hood of the Marmot Plasma 30 is the most comfortable sleeping bag hood of all 11 bags in our Backpacking Sleeping Bag Review. First of all, the edge of the hood/collar has a small passive draft collar-like down filled tube that is soft on the face and keeps the uncomfortable adjustment cords protected beneath. Those ends of those same cords are redirected through a small loop which passes them horizontally and keeps them from migrating inside the bag to get tangled in your face and clothing. We really like how the hood on the Plasma ca be cinched, stay in place, and still be totally comfortable. Some bags cinch the hood to a point that it creates a small hole just big enough to stick your lips out to breath. Sleeping snorkel anyone? The trapezoidal footbox gives feet room to stretch without compressing insulation, especially when lying on your back.
You guessed it. Lightweight materials and high quality, compressible 850+ down allow the Plasma 30 to pack down pretty small. Marmot includes a small nylon sack that packs the bag down to the size of a medium sized watermelon, but a compression sack shrinks it down further to an even more manageable size for shoving into the bottom of a small backpack.
The full length draft tube along the zipper and a fully functional draft collar set this bag apart from the other sub-1.5 pound sleeping bags we tested, and we've already emphasized our taste for the smartly featured hood on the Plasma 30. We like the extra insurance of Marmot's "Down Defender" water resistant down treatment. The Pertex Quantum outer shell managed to bead some water on those dewy mornings at lake level in the high country. One last feature that is obvious on the Plasma 30 is the vertical baffles. It is said that the Insotect Flow Vertical Baffle System aids in transferring heat from your core to the extremities. This movement of heat wasn't noticeable in practice, but we also found no specific fault of the vertical baffles. Down did not shift around and there were no specific cold spots in the bag.
We would prefer a warmer bag to span 3 seasons in the mountains, but with a little extra clothing the Marmot Plasma 30 will go further than its other sub 1.5 pound companions in the review. For a few extra ounces and a couple hundred dollars in your pocket, you can step into the Western Mountaineering Ultralite or Alpinlite which are much warmer and more capable at colder temps at the higher elevations. Those who travel in more moderate climates with a little extra cash in their pocket should find this bag to suit their needs.
We carried this bag on long distance summer backpacking trips in the High Sierra and found it to be a stand out for this application. The Plasma 30 is lightweight, compressible, and warm enough for most nights below 12,000'. Throw on an extra layer and zip yourself inside a tent and extend the season and elevation zone of it even further.
The Marmot Plasma 30 is priced at least eighty dollars more than any other bag in this review. As a single bag to be used in warmer climates year round, it is a high quality, feature-laden, comfortable bag. But realistically, most of our backpacking takes place in the mountains and deserts where big temperature swings are normal, and to extend your season with one bag you need something with a bit more insulation. For a dedicated bag for ultra-light mountain objectives, consider more fairly priced products like the Sea to Summit Spark SP II.
The Marmot Plasma 30 doesn't meet our expectations for a single sleeping bag to span three seasons of use; especially in the mountains, because it just doesn't have enough insulation. However, it was a testers' favorite, scoring high marks across the board otherwise. Our biggest hesitation with this bag is the price-tag. For less money, you can buy a bag that is more versatile or save even more money for an "ultra-light" type traditional sleeping bag such as the Western Mountaineering HighLite or the Sea to Summit Spark SP II for specific objectives where weight and space are critical.
— Mike Phillips