I was really excited to find this product and the prospect of warm food at lunch time. Unfortunately, it just doesn't retain the heat. Even after superheating foods in the microwave, filling it to the top etc, food was tepid just 2 and a half hours later. It is also very difficult to unscrew the lid at lunch time, so would be virtually impossible for kids. I love the design and that you can microwave the food in the container, making it quick and easy in the morning but sadly it just isn't up to the job.