New GPS recommendations...

Garmin.   Last road trip we took (up the coast of California, almost to Oregon) we used the Garmin, the iPad, and printed maps.  Between the two digital systems we always had connection to either towers or Satellites, sometimes we'd lose one, but the other worked.  The paper maps were ones I printed "just in case."   

I actually stopped using my garmin cause i didnt like it. It was a more expensive one. the problem i had was once it chose my route to where ever, if i tried to stray off that course, say to go get a coffee at a dunkins off course, it wouldnt recalculate my " new " route, and would force me to try to return to the " old " route.