Exped sleeping bag temp rating mystery
Hey everyone! I'm looking to get a 3 season sleeping bag for the Scandinavian summer and I stumbled upon some sleeping bag temperature ratings I can't explain. I figured this sub has the highest likelihood of shedding light on it.
tl;dr the manufacturer numbers say "pay twice as much for a less comfortable bag with the same temp and weight"
Specifically, I was looking at the Exped Comfort and Ultra bags. The Ultra is the premium model, promising the best temp/weigh ratio. The Comfort is the "weight isn't that important" model However, looking purely at the numbers that isn't really the case.
For example: The Exped Ultra -5C has almost the exact same temperature ratings as the Exped Comfort 0C (the Ultra is 1C/2F better). This surprises me, as the Ultra contains 60% more down fill, has a narrower cut, and weighs 40g more. Since the Ultra is a premium model and 75% more expensive, the Comfort seems almost too good to be true here. I'd have expected the Ultra to do significantly better than the Comfort.
Exped is a well reputed manufacturer, so I doubt the numbers are just made up. I did contact them but am still waiting for a reply. My guess is that the Comfort achieves better results in lab conditions than in real-world use, but I'm not sure why. If anyone has a theory (and what the actual temp rating should be), I'd love to hear it.
Exped Ultra -5C L
- Temperature: Comfort 1°C / Limit -4°C
- Weight: 960g
- Fill: 540g @ 850+ cuin/oz = 16k cuin
- Price: CHF 559 (USD 700)
Exped Comfort 0C L
- Temperature: Comfort 2°C / Limit -3°C Weight: 920g
- Fill: 410g @ 700+ cuin/oz = 10k cuin
- Price: CHF 319 (USD 400)
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