does any one know about the memory capability of the garmin 60c and 76c. these models look perfect for trail/dual sport use, they are small, easy to read, and rugged. they come with a built in basic map, but i would be interested in a more detailed topo map, such as garmin's map source US topo for navigation while trail riding.
garmin's map source US topo covers the entire US and is based off of USGS 1:100,000 paper maps (it's something that must be bought in addition and downloaded into the units internl memory of 56 megabytes and 115 mb respectively 60c/75c). how much map will either of these units hold on this internal memory? would 115mb be enough to hold the map source topo of an entire state, such as colorado? there is no place to add extra memory such as a compact flash card. any help would be appreciated!