Biometric Analyzer inaccuracies

Just wondering if anyone has ever played around with the handheld analyzer, I put in some modified information about myself (making myself younger and older) to see how different the results would be and there was a big difference in the bf reading. While we all know that we tend to have higher bf percentages as we age, it shouldn't assume that and use that in its calculations. Its almost worthless I guess but the most useful technique I know to use at health fairs and other public venues.

Your input?