There are some sacrifices though in opting for a bag that supplies all that space to move. The most significant possibly being your home heating capacities and heat scores. See, while having all that space is nice, much like having a big house with tall ceilings it takes a great deal even more to heat the within. The added room requires more effort to keep cozy and also for that reason, isn't really as efficient for shutting out the cold as a mummy bag is. Obviously having said that, the pyjamas you prefer to oversleep can aid make up for the heat differences between the bags also ... approximately particular temperature levels. Suffice to claim that artic temps could call for more than a teddy or set of boxers.
The other sacrifice is the size or thickness of the bag. A mummy sleeping bag essentially will certainly be much smaller sized for bring around which is why it is a preference for many backpackers/hikers. The rectangular resting bag isn't as small yet because it's not common to be lugging it, apart from somewhere in a vehicle while getting to your intended location, the bulkiness of the bag is not as large a problem.
Remember that with time, from typical use, a treking sleeping bag will certainly lose its warming performance. This results from the fill obtaining a bit much more compressed. This will cause the "air pockets" to go away.