Of course, the packed size is important: The smaller a sleeping bag is, the easier it is to pack and carry and the more room you have in your rucksack for other things.
BUT:
A sleeping bag that packs up small is light and thin, and light and thin does not necessarily mean warm.
A brief explanation why:
High air storage factor – warm sleeping bag
A high air storage factor in its filling makes for a warm sleeping bag. So, if it is thin and light, it will have a lower air storage capacity and consequently not keep you as warm.
Sleeping bag size – too tight, therefore too cold
The right size of sleeping bag also plays a role: if a sleeping bag is too narrow or too small, the sleeper compresses the filling because the shoulders press on the outer wall. This greatly reduces the insulation capacity.
Grüezi bags are sleeping cosiness, warmth and comfort all rolled into one
We measure our sleeping bags from inside. This is what you’d get if you measured from the outside: " 6-10 cm more". (Depending on model!)
Our Grüezi bag sleeping bags are generously cut, considerably more spacious and therefore completely comfortable for the user.
Every gram is twice as heavy if you sleep badly
Sleeping comfort is usually more important than a light weight. If you are tired and badly rested, every gram of weight that you have to carry the next day is even more of a burden. On the other hand, when you are well rested a few grams of extra sleeping bag weight are not an issue.
You should therefore make sure that you choose a sleeping bag suited to your activities; one where the temperature indications, and in particular the Tcomf comfort values, are suitable for the trip you are planning and that the material provides an excellent sleeping climate.