Should I “update” my Roadmate Magellan GPS

pnichols wrote:
which makes me doubtful of it uses satellite access for anything accept locating us if we can make a regular cell call for some kind of help.

While the evidence that you have seen might logically make you think differently, the recent "smart" phones actually have a GPS chip in them. The phone/data network is used to get the maps but isn't needed again until you go a LONG way down the road and need a new section of maps. Unlike a "real" GPS, it won't store the entire map of the US, for instance, all at once.