Use a GPS tracking key to create "Duration of Stop" data?

Land Air Sea GPS Tracking Key

The main feature of this product that is of interest to me is the ability to record "Duration of Stop".  This would help keep track of time spent at various clients during the day and provide data for billing for time spent on site.  The supplied software integrates with (and relies on) Google Earth to produce the results. The software is erratic at downloading data from the key.  Sometimes it doesn't recognize the key.  Occasionally it claims there's no data to download, other times the data downloads OK but is corrupt and unable to create reports.  The Google Earth integration quit working.  There's no power off/on switch, so it uses AAA batteries every week or so.  There's four very small screws next to the magnet base that need to removed every time the batteries need changing.  The tiny screws are easily attracted to the magnet and are easy to loose if dropped.  Overall, the product is a great idea, but the hardware and software both need improvement.