I have been using one of these biometrics for a little over a year. I like it, it holds 15 prints, has a battery back up to the AC, and a mechanical key to override the reader. The only problem I have is during the winter months my dry skin seems to make the reader not work so well. When my hands are real dry, I need a quick swipe on my tongue first before swiping the reader, just to get a little moisture on the pad of my finger (not as gross as it sounds, not a slobbery swipe).