purchase this gizmo for my laptop chart software , the gp work very well , acquire signal fast and accurate . I could not make it work with my software but believe be a glitch with it and not the gp . however not all be lose as I can still chart the current position on the chart by just transfer manually the lat and long value . I think be a amazing little wonder and with a appropriate electronic laptop base chart software can easily replace the more expensive package offer for nautical use .