>Try to reach a destination only 30km away
>Plot a route in Google Maps
>Try to memorize it
>Fail miserably, end up in the middle of the woods twice
>Pic related is my current setup (the compass, yes)

So, /n/, i need to get a navigation system.
These are some examples i looked at:

Garmin Edge 520
>Destination can only be entered via Computer/App, not on the device, wtf

Garmin Edge 820
>Everyone says software is terrible and unreliable

Sigma Pure GPS
>No map navigation, only arrow pointing to destination, would have considered that if it could save more than one destination

Sigma Rox 12.0
>My prime candidate so far, although it's a bit overkill

Most of these have way more featues than i need (tons of stats, sensors, online stuff like Strava), my prime concern is navigation, i.e. finding a destination.

So I wanted your input:
Do you have a Bike computer with navigation?
How does it work for you?
Bonus points for Libre/FOSS, or at least it should work with Linux.