Here is how these two sleeping bags compare on the numbers. The Hummingbird YF 20 takes a modest overall edge, led by low weight, but the Swallow YF 20 has its own case.
| Feathered Friends Hummingbird YF 20 | Feathered Friends Swallow YF 20 | |
|---|---|---|
| GearScore | 87✓ | 86 |
| Comfort rating | 30 °F | 30 °F |
| Weight | 26.1 oz✓ | 29.2 oz |
| Warmth-to-weight | 5.4 /100g✓ | 4.8 /100g |
| Packed size | 9.0 L | 9.0 L |
| Fill power | 900 FP | 900 FP |
| Price | $569✓ | $589 |
| Fill | Down | Down |
| Style | Bag | Bag |
| Shape | Mummy | Mummy |
Highlighted cells mark the better spec: Hummingbird YF 20 in blue, Swallow YF 20 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 Feathered Friends Hummingbird YF 20 against the Feathered Friends Swallow YF 20 is a study in priorities. The Hummingbird YF 20 wins on low weight and warmth-to-weight, and the Swallow YF 20 pushes back on value.
The Hummingbird YF 20 is 3 oz lighter, stronger on warmth-to-weight, and $20 cheaper. Their GearScores land within a couple of points (87 vs 86), so neither runs away with it.
Pick the Hummingbird YF 20 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 Swallow YF 20 if you would rather save the difference.
The Feathered Friends Hummingbird YF 20. It is 3 oz lighter than the Swallow YF 20.
The Feathered Friends Hummingbird YF 20. It is stronger on warmth-to-weight than the Swallow YF 20.
They are nearly tied at 87 and 86 on the default algorithm, so re-weight the score to your own priorities to break the tie.
It depends on your priorities. Go with the Hummingbird YF 20 for low weight, or the Swallow YF 20 for the price. The spec table above shows exactly where each wins.