Therm-a-Rest Hyperion 20 Review

The Hyperion is a great choice for warm-weather, lightweight backpacking adventures. If you’re looking to move quickly with a lightweight pack, this could be the bag for you.

Performance Comparison

Warmth

Because it is a unisex model, the Hyperion’s temperature rating is different from the other bags in this review. Therm-a-Rest rates this bag to the EN “Limit” rating, which in this case is 20F versus the “Comfort” rating of 32F. This is different from the other women’s specific bags we’ve tested, which use the “Comfort” rating in their naming conventions, but seems to be the way that Thermarest rates all their bags. This is definitely something to note when you’re comparing the Hyperion to other products in this review. This bag’s Comfort rating is to 32 F. We took it out on a chilly September night and we’d say that rating is just about right. As the temperatures dipped towards freezing in the wee hours of the morning we felt chilly but never cold. We like the Hyperion’s half zip as it prevents drafts coming through the zipper and its snug hood does the same.

Weight

The Hyperion blows the competition out of the water in this category. Weighing only 19 ounces it’s half a pound lighter than its closest competitor. As we mentioned in the warmth section, the Therm-a-Rest Hyperion trades off some of its warmth for those extra ounces.

Comfort

Again, in an effort to slim down the ounces, the Hyperion has a trimmed down silhouette that makes for quite a snug fit. We tested the “Small” size and our 5’5 tester just barely fit length-wise. She was able to get the hood over her head and was quite cozy; however, we think most folks who aren’t used to a snug mummy fit will not feel comfortable in this bag. There is very little legroom (your legs are essentially pinned together in the bag), but there is an articulated foot box so your feet don’t feel squished. This bag is all about its low weight, and you sacrifice comfort noticeably for fewer ounces. We do think that this snug fit helps keep the warmth in. This bag also only has a half-length zip and some people will find this less comfortable as well.

Packed Size

This bag packs down to a tiny little capsule and gets really small. We like that the Therm-a-Rest Hyperion comes with a compression sack to make it even smaller than a traditional stuff sack would.

Features

The Hyperion’s features are all about weight savings, which we think is great. It has a really high quality down fill of 900, which increases its warmth to weight ratio, and the half-length zipper shaves a few grams. This bag also comes with “SynergyLink™ Connectors” that are essentially removable straps you can use to attach your bag to your sleeping pad if you’re one to roll off your sleeping pad. We really like that they’re removable and appreciate the simple attachment system.

Value

Even though the Hyperion has high-quality materials, we think the price tag is a little steep. There are other products in this review that you get a lot more bang for your buck than with the Hyperion. However, it is one of the lightest bags we’ve found that’s sized for smaller people. If the conditions and mission are right, it could be worth the money for you.

Conclusion

The Therm-a-Rest Hyperion is a great choice for fast and light summer adventures. This is a very snug-fitting mummy-style bag that’s comfort rated to 32 F, so be sure you’re ready to sacrifice a bit of comfort and warmth for a tiny, lightweight package. If you’ll be spending lots of time carrying your stuff around, and don’t think the temperatures will go below freezing, this bag could be a great choice for you, if you’re willing to pay the price.