We use a little Garmin Quest in our work truck. It's in the price range and its a small unit. Can fit in your pocket. It has voice commands. We us it in California, Nevada and Arizona and we haven't been lost yet. The only bad thing about the unit is that it only has 110MB of memory without an external slot. We have all of Arizona, Nevada and California from Sacramento down loaded in it. I took it to Hawaii and had to delete some of the Ca maps to the load the Hawaii maps. It's easy, like transfering pictures back and forth from a digital camera