It is most unfortunate that Garmin bought Delorme and killed Street Atlas. The charts are now old and nearly useless, but a better planning and enroute navigator has never existed. When running with a GPS puck, you have a big map on a laptop with a "You Are Here" arrow. You know the distance to the next stop be it for fuel or end of day.
If I make up a plan, I can tell you the hour we will be where... If we change a plan mid-day, the change will wrinkle thought the plan so what is projects is now correct. This can alert you to changes in fuel or EOD long before it is critical.
Anything web-based is useless as you will loose the connection sometime that you need it. I have worked with Google and Furkot and lost connections all the time. Neither can be counted on while underway. I even preloaded the Google maps only to run off the edge before we regain coverage.
Yes, GM on the phone will be realtime, but it will project the changes required to the days plan.
Sorry to sound like a "Good Old Days", but I can only imagine what SA or S&T would be like if five years newer. It could be linked to the coaches systems to look for cheap fuel on GasBuddy and make the campground reservations all autonomously and only ask for approval.
Matt