It kind of depends, IMO.
I have been playing around with GPS for a while and my current feelings about it are "it is something of a distraction - a useful distraction at times, such as when running about in an unfamiliar city, but a distraction overall".
With two, or more, of you in a 4 wheeler it need not be such a distraction - more a plaything perhaps - but on two wheels, that it is how I see things right now.
So, that doesn't answer your question, but, hey, you can read into the forum for Maroc Morocco - The HUBB
to get more ideas + this forum about navigation in all of it's aspects
Basically, it rather depends on what you want to do there and where you are going and how you intend to use the highways/pistes - lots of variables in other words.