gros21
Hard to say what maps you will see on your unit in Australia, if Navionics has a map system for your area it will be in your best interest to find out what lakes and rivers (if any) are on the chip. My guess if there are paper maps available, it would be best to use these charts to gather waypoints and input them into the HB unit.
I have found that the local maps have information available that Navionics does not include on their SD chips. I have purchase the platinum mapping program, pus purchase all available maps for the lake I fish and use the paper maps to help locate special areas. But most of the work has to be done by myself.
George
George