I don't need the new model's color screen as I did get a cable that plugs the GPS into my old Compaq iPAQ. It'd be a bit much to carry on a hike but that's not really the goal as the cable allows both devices to plug into a single cigarette lighter.
That wire plus the pocket version of Microsoft Streets and Trips gives me color. I watched the little circle stay in the center of the map as I drove along major and back streets. It was a little magical and it was a lot dangerous as one cannot really watch a screen and out of the windshield at the same time!