I run a $200 ALDI GO CRUISE to navigate and it works fine almost everywhere I go
My older Garmin Map76 runs Mapsource that I got with it and it is crap offroad, but,,,
I do run the SHONKY LOGIC full topo on that unit as a backup and it is terrific as far as detail & tracks go
I also use the Shonky maps in my pc to plan routes, mark them in and then print and laminate maps or just sections that I need, that I can stick in my tankbag for any tricky intersections etc

Comes in handy
It would have to be the best free one out there for sure ,,,,,,