One point mentioned but IMO not emphasized enough is "Where is the database?"
If it's in the cloud, then maps are downloaded as needed
IF cell data is available. On long road trips off interstate highways that may not always be the case. Even near interstates that may not always be the case. I was in Tomah, WI a few years ago using an MVNO connecting to the AT&T network and had no coverage. Two interstates intersect at Tomah.
If the database in the GPS program/local, then no worries about being out of cell range, but the database will be out of date to some degree. If I was a realtor working new developments this might be a problem for me. Going from Chicago to Boston, probably not so much as they have not moved recently.
Google sort of has a foot in each camp, caching some map data for local areas recently used. But that won't help on a trip to/through new territory.
Our GPS of choice is not on the list. CoPilot (
https://copilotgps.com/en-us/) features downloaded maps. In addition to the US and Canada which was included in our purchase, one can buy and download maps for most areas of the world though third-world coverage is spotty.
Our second choice GPS is Google, primarily for the traffic information. Where we're concerned about traffic we are in a city, so cell data is pretty much available. CoPilot has a traffic option, too, but there is some kind of fee.
So ... IMO the location of the database should be considered versus someone's use case for the GPS. Tradeoffs will differ.