I recently purchased my Dusky with a 1724C chart plotter/Radar and a fCV585 fish finder. I need to get either a Navionics card or a C-map card. I will make sure the 1724C has the latest update to the S/W. I fish the Florida Panhandle and the Florida Keys. I am having trouble determining which compatible card to buy. I haven't used C-maps before. According to the Navionics site the 1XG version is not compatible (which covers the area) with my 1724C, but I don't see another card that covers the gulf. If any one has a recommendation, please help.