Here is how these two sleeping bags compare on the numbers. On the data the Flex 22 is the stronger all-round pick, and the question is whether the Neutrino 400 still fits your budget or priorities.
| Katabatic Gear Flex 22 | Rab Neutrino 400 | |
|---|---|---|
| GearScore | 86✓ | 66 |
| Comfort rating | 32 °F | 30 °F✓ |
| Weight | 23.9 oz✓ | 27.3 oz |
| Warmth-to-weight | 5.6 /100g✓ | 5.2 /100g |
| Packed size | 8.0 L | n/s |
| Fill power | 850 FP✓ | 800 FP |
| Price | $409✓ | $435 |
| Fill | Down | Down |
| Style | Quilt | Bag |
| Shape | Quilt | Mummy |
Highlighted cells mark the better spec: Flex 22 in blue, Neutrino 400 in amber. A blank spec is never counted as a win. A lower comfort rating in °F means a warmer bag, so the warmer bag takes that row. GearScore is the overall rating (0 to 100); re-weight it on the full bag comparison. Prices are current MSRP.
The Katabatic Gear Flex 22 against the Rab Neutrino 400 is a study in priorities. The Flex 22 is the stronger pick on most of the specs that matter, while the Neutrino 400 makes its case on warmth.
The Flex 22 is 3 oz lighter, stronger on warmth-to-weight, and higher fill power (850 vs 800). The Neutrino 400 is warmer (rated 30°F vs 32°F). On the default GearScore the Flex 22 leads 86 to 66.
Pick the Flex 22 if you care most about low weight and warmth-to-weight, which makes it the better call for counting grams on long miles. Pick the Neutrino 400 if warmth matter more to you, or you are focused on colder nights and shoulder-season trips.
The Katabatic Gear Flex 22. It is 3 oz lighter than the Neutrino 400.
The Rab Neutrino 400. It is warmer (rated 30°F vs 32°F) than the Flex 22.
The Katabatic Gear Flex 22, 86 to 66 on the default algorithm. You can re-weight the factors to match your trip.
The Flex 22 is the stronger all-round pick here. Choose the Neutrino 400 if warmth is your priority.