On the V-20 I hava GPS and a compass.
Generally I use the compass but, I've been in weather that would be hard to tell which way I was going w/o the GPS cuz the compass was spinning around. Clouds rain and waves in the dark made it impossible to otherwise know the way back.
Sure is nicer than the ol'RDFs.

In my neck of the woods you cannot do without a compass.That is of course the south west of Ireland,{check it out on google earth}so many islands and rocks.If you get stuck out there in fog or poor visability and you have no compass you are up the perverbial creek!!

I checked it out on G'Earth. Looks like a nice place for boating, Lotza protected water. I can imagine in a thick fog it'd be hard not running into something.