I just load a GPX file a knowledgeable mate has made into my XT and ride. We sometimes pull over whilst the two lead riders argue over who’s unit/which way is correct, despite them all using Nav 6’s with the same GPX loaded.
If I get lost on my own, I follow the thing to the next hotel. If there’s a drama back home I set it to Calais and ride like fuck.
I’ve done similar with a TomTom Rider and a Zumo 660.