do you have a nema network in your boat already. If so the marine radios that work with nema 2000 are easier to hook up. You can get gps data for the distress button. Standard horizon does have a model with built in gps. Many people have had trouble getting the old 183 systems working right with the new locators. Enough people have used that distress button without ever hooking it up to gps. Coast guard did not get their gps numbers.