GEAR REVIEW: Big Agnes Mystic SL 15 Sleeping Bag and Q-core SL Sleeping Pad

Disclaimer- I will never review an item I have not personally used on a trip.

BIG AGNES MYSTIC SL 15 SLEEPING BAG

& BIG AGNES Q-CORE SL SLEEPING PAD

After backpacking Yosemite with the Big Agnes Mystic SL 15 and Q-core SL together, I have fixed feelings. The comfort is amazing, but the system is heavy for what it should be.

Design: The Mystic SL bag is not your typical mummy sleeping bag. The foot area is squared off, leaving plenty of room to stretch out your legs. I’m a side sleeper, preferring lots of room to toss and turn. This bag has the room and then some. Oh, and it doesn’t have a bottom.

“Huh?”

Yep, the bottom is a simple sleeve, where you can slip a sleeping pad into. Unlike a quilt, it is sealed. The benefits are this: the sleeping pad acts as the insulation on the bottom, saving fill weight and packed size.

The hood area is comfortably loose, offering a drawstring to tighten it for the cold nights.

Paired with the sleeping bag is Big Agnes’ Q-core SL pad. Unfortunately, the Mystic only fits the 20” version, as much as I would have liked a wider pad. The pad inflates as well as an inflatable pool toy, but that is to be expected. The comfort though, is very nice. The baffles are placed in an I-beam formation that made feel odd at first if you have spent years sleeping on other pads, but it is soon forgotten. The thick 3.5” pad has plenty of buffer for when I turn on my side. I didn’t feel like I was hitting the ground each time I turned. The sides held up well when I got close to the edge. The pad comes in a mummy shape and a square shape, so you have to get the one that matches your bag. In this case, I had the square one to fit the square foot box of the Mystic.

Specifications:

https://www.bigagnes.com/Products/Detail/Bag/MysticSL15

	regular/up to 5'10"	long/up to 6'6"
Pad Size	20"x72"	20"x78"
Color	black/green	black/green
Fill Type	800 fill goose down	800 fill goose down
Fill Weight	15oz	16.5oz
Bag Weight	2lb 4oz	2lb 7oz
Shoulder Girth	70"	73"
Hip Girth	66"	69"
Foot Girth	54"	55"
Stuff Sack Size	M-8"x17.5"	M-8"x17.5"
Compressed Bag Size	8.5"x8"	8.5"x8.5"

https://www.bigagnes.com/Products/Detail/Pad/qcoresl

Size	Color	Rated To	Weight	Price
20" x 66" x 3.5"	Orange	15°	16oz	$139.95
20" x 72" x 3.5"	Orange	15°	17oz	$159.95
20" x 78" x 3.5"	Orange	15°	19oz	$169.95
25" x 78" x 3.5"	Orange	15°	23oz	$219.95
20" x 72" x 3.25" mummy	Orange	15°	16oz	$159.95
20" x 78" x 3.25" mummy	Orange	15°	17oz	$169.95

Here is where the Big Agnes products disappoint. The Mystic SL was supposed to be the superlight version of their old Mystic bag- hence the ‘SL’ tag. Unforunately, their upgrade was only to 800-fill down. I would gladly pay the extra money to get a 900-fill version of the same bag, saving me ounces. That’s where the next disappointment comes in- The Mystic is missing an ENTIRE SIDE of fill, thanks to the Big Agnes system, yet it still weighs in at a whopping 2 lbs 4 oz (Regular length). They don’t give a weight in grams, but assuming that is accurate, that would be 1020 grams. When I weighed mine, it weighed in at 975 grams. 

Where it had lost the 1.5 ounces, I’m not positive. The stuff sack weighed in at a similar weight, so I’m guessing they included it into the weight of the bag. Even then, the bag weighs over 2 lbs. Two pounds and it is missing an entire LENGTH of fill weight. I would expect a bag that has half the down to weigh less than two pounds.

Now, for the much debated Q-core SL pad. People have complained it was narrower than the original Q-core, and even shorter. While I had never owned the original, I did notice the pad seemed narrow. In the end, it didn’t matter as it fit the sleeve of the Mystic near perfectly, and any wider and the pad would not have fit. Now, after reading all the complaints on forums about this issue, a simple answer occurred to me: I assume this is to compensate for the wider pads that other people might shove in there, that would be half as thick. A 18”x3.5” pad fitting snugly into a sleeve that would fit a 20” x 2” pad.

My disappointment with the pad is the weight. The listed weight for the pad I have (20”x72”x3.5” Regular) is 17 ounces.

On what broken scale they weighed that mess, I have no idea.

My pad (without the mesh sack) weighed in at over 19 ounces (540 grams)! Instead of being on even ground with the Exped Synmat UL, it turned out to be much heavier.

Now, I’m not the biggest stickler on weight, but 3 ounces is a deck of cards. It’s an extra pair of socks. It’s more FOOD. Don’t mess with my food.

Those extra two ounces are taking up my food weight, and I don’t like things taking up my food weight.

I’m not sure why they advertise the weight that low, since there is nothing to cut off the pad. It is what it is, and there are no shortcuts there.

EXPERIENCES: Now, this is the second set of my mystic/q-core combo pack. The first set I got were actually in the ‘long’ versions. I typically like more leg room, and since I had opted for the heavier bag/pad combo anyways, I figured I would go for the full comfort.

Fortunately the bag is so roomy, I didn’t need that extra length. It was extremely comfortable, even towards the lower temperatures. The last night in Yosemite dipped low enough I got chilled, but quickly realized it was because of all the dead space I had down by my feet. When I returned home, I sold my bag and pad on Craigslist, then turned around and bought the regular length versions of both. While I have not used the regular in overly cold conditions yet, the regular kept me warm both nights I have slept in it. I still had room enough to stretch my feet out, even though I’m six feet tall. The interior was wide enough to let my 170 lbs frame room to toss and turn without feeling compressed. The one thing I will be watching for is the temperature. 15F should have been good to anything Yosemite could throw at us during September, but it was with a longer bag and no sleeping layers (I prefer to keep the sleeping layers for when it dips low, so I’m not wrapped in a sweat box during the nights that aren’t cold).

While I could easily drop a full pound of weight by switched to a Feather Friends Hummingbird 20 and a Thermarest X-lite pad, for now I plan to keep the extra weight and the comfort it affords, allowing me a good night’s rest. An extra pound during the day is worth ten pounds on a sleepless night.