Big Agnes Mystic SL Sleeping Bag Review

Having a good sleeping bag can sometimes make or break a camping trip. Since sleeping outside limits the amount of sleep we get compared to a comfortable bed, I try to find anything that helps me get a better sleep. After all, when you are camping you are typically headed out for some sort of activity the following day and you need all the sleep you can get.

Sleeping bags range in price from $25 to $500 for a 15 degree sleeping bag and often times you get what you pay for. In this case, the Big Agnes Mystic SL ranges between $390 and $410. The price tag itself is usually going to rule out those looking for a good deal at Walmart, but for the outdoor enthusiast who won’t sacrifice quality for price, the Big Agnes Mystic SL is a must to take a look at if you are in the market for a new sleeping bag. I know a many of you are saying to yourself that you wouldn’t pay that much for a 15 degree bag and that is one of the reasons I wanted to test it out. I wanted to see what this bag was all about and if the quality and technology matched the price.

The Mystic SL uses an 800 down fill for its insulation which allows the sleeping bag to provide plenty of warmth and loft while reducing weight and size. My rule of thumb has typically been not to use a sleeping bag under 600 down fill as I like to reduce some weight and size when possible. When you start using down fills in the 800’s, the price goes up a fair amount as this type of down is harder to come by for manufactures and you are typically receiving greater benefits.

The underside of all Big Agnes sleeping bags have no insulation to them. It is typically a thin layer of fabric that separates your body from the tent floor. Instead of using an insulated bottom, Big Agnes uses a slot on the underside of the sleeping bag where you can slide in an air mattress. As you might imagine, Big Agnes has there own line of camping air mattresses, but other popular air mattresses like Therm-a-rest typically fit as well. These air mattresses create a layer of air between you and the ground and often have some sort of insulated property. On the down side, if you end up using a larger air mattress like a full or queen size, it takes a lot longer to heat up the air inside and therefor, your bottom side can get pretty cold depending the outside temperatures.

Draft collar

The Big Agnes Mystic SL has a rectangular shape, so if you are one of those who get claustrophobic in mummy bags, this is a nice alternative. I am 6’0 tall with semi-wide shoulders and I like a rectangular shaped sleeping bag verses a mummy bag. I also like having the ability to move my feet around too. Since I often flip flop when I sleep, having enough room to turn over is nice. The draft tube along the zipper is made of a thicker material. By using a thicker material, the zipper gets caught less and the chance to tear your sleeping bag due to a zipper snag is significantly reduced. The Mystic SL also has a nice draft collar along the face opening of the sleeping bag; this can really come in handy when the temperature drops and you need to preserve all the heat you can.

Rip resistant material by zipper

The outer material in the Big Agnes Mystic SL sleeping bag is made of Pertex Quantum rip-stop nylon. The Pertex Quantum fabric is an extremely lightweight material that helps reduce the weight of the sleeping bag. And while lightweight is often a good thing, you do have to be a little more careful since this material can tear a little easier. The only time I have actually had Pertex material rip on me is when my down jacket caught a rose bush, but I usually try to be a little more careful with this material. I have my dog Aspen to blame for that one…  There is a sown in pillow sack in the head section of the Big Agnes Mystic SL where you can stuff a pillow or other clothes that you haven’t worn to work as a pillow  I suggest not using the clothes in which you sat next to the camp fire all night long. The Mystic SL weighs in at 2 pounds 4 ounces which is super light for a 15 degree sleeping bag, but it must be noted the lack of insulation on the underside of the sleeping bag.

The Mystic SL uses what Big Agnes calls Flow™ Construction: Insotect Flow™ for insulation management. This in essence keeps the down from clumping up and creating cold spots. For the time I tested this sleeping bag out, I couldn’t detect any clumping, but if the down started to clump up, it would typically happen after multiple uses a year or two later.  One thing that I would have liked to see in the Mystic SL is a zippered pocket in which you can stash a small item or two. This probably would not play much of a factor in my purchasing decision, but I like it when a sleeping bag has a little stash pocket. Outside of no stash pocket, I enjoyed testing out the Big Agnes Mystic SL. It is a perfect option for the outdoors person that is looking to shed a little bit of weight while maintaining a high quality sleeping bag. For more information on the Mystic SL and other Big Agnes products, please visit www.rei.com.

Specs