I just replaced the Garmin GPS III+, which I had in my truck, with the  ColorMap. The screen is much easier to see in a variety of lighting  conditions. The ColorMap also changes some of the field colors, depending  on the time of day, to provide ever greater visibility. This unit is really  designed to be used in a vehicle and provides features to that effect such  as a readout stating which road your currently on. This is much easier than  trying to find the road label while you're driving along.