yair! I used to have some of those body fat scales. I doubted their integrity. If you read the instructions you can't check your body fat/water etc first thing when you get up????
Maybe your fat is in your feet and it will tell you something different? They apparently send a pulse through your feet to measure fat and water and then does some sums with your weight. All a lot of smoke and mirrors to me.
It least they told me my weight in big letters... why did they die?