This is an ideal size for one person wanting to carry chunky soups. I bought it today and although I have not used it I have done a thermal test on it. I was concerned that if there was too much thermal loss the contents could become the ideal breeding ground for bacteria. I preheated the jug with hot water and then filled it with hot water. The temperature of the water was 95ºC at that time. I then put it outside in an air temperature at 6ºC at that time. I left it outside for 4 hours and the temperature had dropped to 2ºC. The water temperature had dropped to 50ºC which is lower than I would have liked however the air temperature had been lower than a jug would experience in a rucksack. I will be happy to use it to keep soup or other liquids hot for 3 hours but no longer than that