How will he wear it? I wear mine on my belt or use a pocket clip, so either way my ACUs hide it. A bright color may not be a bad idea. If you get him a tan one, it might be hard to see in the sand.
BTW, I purchased an Emerson CQC-10, and it's stood up against all the dust and sand, although I don't go out on missions outside the wire much, so that with a grain of sand : ).
Where's he going, if you don't mind me asking?
Dan