Down filled sleeping bags are a much more compact and lightweight alternative to sleeping bags with a synthetic fill. Down has many great properties that make it a wonderful insulation for sleeping bags but this does come with a price. Down offers the highest loft to weight ratio meaning that you will keep much warmer with much less filling than you would with standard synthetic filling. It achieves this by efficiently trapping warm air within the sleeping bag and providing much better insulation. Down filling can come in the form of duck down or goose down and they can be rated on their performance by fill power. 600+ is usually recommend as a high quality performance down sleeping bag and many of our Vango Venom down sleeping bags are filled with 700 fill power down meaning you know you can really trust the quality. The main reason to choose a down sleeping bag would be purely on the pack size and light weight that it can achieve. As it needs less filling, down can compress down much smaller than synthetic filling and will be much more lightweight. This makes them great for extreme adventures, hiking and mountaineering.
I recently went camping in scotland , the temperature was a little over freezing , i found the bag to be reasonably comfortable and warm , i had a great nights sleep , i also tried the mosquito net , i found the zips a little hard to do as the bag does not have much room to manoeuvre around in , once the net was zipped up the bag felt too claustrophobic for me to sleep all night with it done up, however had there been a true need for the net im sure i could have gotten used to it , the only issue i had was the bag it came in is very poorly made & the stitching broke the first time i rolled it up and put it away , overall i am happy with my purchase and would recommend it to any casual camper for short term use.