Older radios Drop might not meet todays performace/waterproof specs, but the frequencies are the same
The difference between older/newer radios will be the addition of the DSC feature, Ch 70 is the hail frequency for the DSC feature. Maybe some auto switching when keyed and I know that Standard Horizon has a feature via NMEA connection with a VHF that will plot another's position on the chart.
All depends,, dont know exactly how old your radio is, but like computers, electronics seem to become out date every couple years....
if on inland lakes/freshwater type locations near land, you probably dont need a VHF with all the bells and whistles.. plus it will save you money as well. All of todays radios are very good, but the radio is only as good as the antenna connected to it, so I'd spend more $$ on the antenna than the radio unit.
Should be no limits or access problems. VHF is VHF, frequencies are set.
