Some folks I know have are interested in getting a GPS unit that can route around things like low overpasses, tunnels with hazmat restrictions & such; things RVs don't like.
Of course, my first advice would be to save your money, don't rely on that junk, and know your route, but I have a feeling that advice ain't gonna fly. :)
Any recommendations or leads?
I'd tell them to get the truckers edition of the Rand McNally Road Atlas.
IIRC It has the low overpasses, tunnels with hazmat restrictions & such as many trucks don't like them either.