Having a GPS Unit while travelling seems old fashioned these days because of our cell phones. However, they can save you a lot of money and frustration because a GPS unit does not need an expensive mobile phone data plan or wifi signal. You just need to have the right maps, turn it on and it just works. This is why I always bring my old Garmin GPS unit when I travel. Read on to see why I purchased a Garmin GPS and how I learned to switch the maps on my Garmin Nuvi GPS.