I have had this for about a week now... wanted to use it before writing review. I had a little difficult with the instructions to set up for multiple users and set age/height. But once I figured out the logic, seems pretty simple. If you jump on scale before it is ready, will get an error and pretty weird numbers. SO, be patient and wait for it to be ready to process for selected user. SO.. once you undestand all that, it works as would be expected. (Using just in weight-only mode is simple--not complicated). I have been tracking the numbers (weight, %fat, %muscle, %water, BMI) for several days. There is a fluctuation on the % readings... but I averaged them and feel ok with the results. I compared this model to others that provide the % and BMI numbers. This seems to be the most inexpensive model that does these tasks. I'm pretty happy with this OVERALL. The only reason I did not give it a 5 is that I have high expectations and the materials seem a little less expensive... but compare the value/cost to other models... this is right on the money.