Some good info already on here, Dan hit the nail on the head with the mapping. Garmin buys the map from a 3rd party, and as good as they are, they aren't absolute! For instance, we are now in TX, and they have the outer roads that run on each side of the interstate, as one way on each side of the interstate. The GPS will have you get off on an exit, and when you do, sometimes it still "sees" you as being on the interstate, so if you aren't paying attention, when you exit you may miss your turn, as it's got you going to the next exit (this may be the GPS/Garmin's fault). Also sometimes we've had it tell us to exit off the interstate (this has happened in CO, and other states), and at the bottom of the exit, it will have us get right back on the interstate! Also, when going through a major city, for instance Dallas, it will have you go right through the city instead of taking the loop around the city & away from the major traffic. My wife always has a state map in her lap to verify what the GPS is telling us...it's saved us several times! We have a Garmin Nuvi 750, it's outdated & we need to replace it, but just haven't found that round tuit yet! We also own Garmin hand held GPS units for Geocaching & from what I've heard from numerous people Garmin is the best for Geocaching. Do a lot of research on them & learn as much as you can before you decide which one will work best for you. One of the best ways to learn how to use your GPS whether you are using it in your vehicle, or in the woods is to Geocache. You'll learn your GPS, and have a lot of fun on the way!