Am a user of an old PDA and am running OziCE and a Natmap that is Aprox 700MB of NatMaps Australia "I have the orig Disk of Natmaps and that file was about 3GB file" with this also on a laptop for serious Map work and being able to download from the Mines Department "Department of Industry and Resources of Western Australia" am able to load and calibrate full 250k:1 PDF map of Tenement maps and be within 4 Meters of my location. Is nice to be planned and accurate.