I have a downtube fender I've used for my mountain bike. It was good for keeping mud out of my face, but that's it. I think full coverage on the rear wheel would be great because when going through sand, the rear wheel throws a lot of it onto my legs and into my shoes which is very annoying.
The "reacharounds" (tee hee) look awesome and is pretty much what I'm aiming for. I'm pretty sure I can make something like that and make it look good. Thanks for the suggestions everyone.