We are about to take possession of a 2000 model R72, in Australia, and want to know if we can, and how to, use a handheld unit like Magellan with the Fieldstar system, and whether or not we still need to deal with differential signals. We are far from the coast, but do receive clear FM radio signals (if this is relevant info). We have just upgraded from a '94 R62. local gps reps are wondering the same thing. We would be grateful for any suggestions.