there's been many a time i've been out in the middle of nowhere with a friend or family member and google maps stops working on their phone, and i get to pull out OM and save the day :^)
Is open street map data pretty accurate? I don't expect google mas level of accuracy but I think its important that I can rely on the maps when I don't know anything about where I'm at
I did a month long trip around western Europe (Italy, France, Spain, Netherlands, Germany, Denmark and Sweden) and used Organic Maps as my only navigation app. Worked well for everything I used it for. Even the metro data was accurate. Also, in my home country, Estonia, it's even better than Google Maps, because it has bike navigation integrated.
Forgot to add, that it also gets updated faster than Google Maps. A roundabout that was built, took about a week to be added to Organic Maps, on Google Maps it took more than a month.