Update: I was able to use my Librem 5 and Pure Maps for navigation throughout my trip. As general purpose navigation tool it did the job, and after using it for almost a week here are the things that still need improvement:
* GPS would drift 60-100 ft sometimes, moving me off route. Probably a L5 GPS sensitivity issue.
* Ability to route to a specific address instead of search.
* General improvements for search in an area (find gas stations/food near me).