In my not-so-humble opinion, Mountain Hardware’s suggestion that their super gear has contributed to Ueli Steck’s accomplishments is utter nonsense. They specifically hint that Ueli’s gear has surpassed Reinhold Messner’s gear. But when he soloed Everest without bottled oxygen, Messner used:
1. Custom-made titanium crampons to his specific measurements.
2. A custom-made titanium ice axe to his specific measurements.
3. A custom-made tent to his specific measurements that was too small for him to stretch completely out.
4. A custom-made sleeping bag filled with Eider down.
5. A custom-made full-body suit including integral hood filled with Eider down.
Ueli Steck could probably not afford such super-light gear. Look to his physical condition to find the source of his accomplishments, do not look to his gear, IMHO.
"The Common Eider, Somateria mollissima, is a large (50–71 cm body length) sea-duck.
The eider's nest is built close to the sea and is lined with the celebrated eiderdown, plucked from the female's breast. This soft and warm lining has long been harvested for filling pillows and quilts, but in more recent years has been largely replaced by down from domestic farm-geese and synthetic alternatives. Although eiderdown pillows or quilts are now a rarity, eiderdown harvesting continues and is sustainable, as it can be done after the ducklings leave the nest with no harm to the birds."