I have one and honestly, it's not all that great. There are so many variables that affect the result you get, that it really can be a pain. They give false high results for most people, especially women. The body fat measurement depends on things like your hydration level, whether or not you've eaten recently, your body temperature, and a whole host of other things. It's very finicky. If you can be very consisten about the way you use it, it is a good tool for tracking changes - but don't accept the values as absolute. Use them only for comparitive purposes. I think several people here have had much better results with the Omron handheld body fat analyzer.