This Garmin dēzl 770LMTHD 010-01343-00 GPS features lifetime map and traffic updates and customized routing based on the size and weight of your truck, so you can easily determine the appropriate route for travel.
For example, I-80 at Sparks, NV. Exit 19 takes me to the TA, but Garmin wants me to take exit 20, which - because I live in Sparks, I know will route me into a Roundabout that trucks get trapped in all the time. If I don't take its recommended exit (which I don't), and stay on exit 19, and at the light that is 75 feet from the TA's fuel line entrance, it either tells me to take on-ramp up ahead (which returns me to freeway), or take left onto a street that will eventually take me back to freeway. I would say only purchase it if you already have a good idea how to get to your destination, though perhaps a bit hazy on details, but DO have the ability and experience to see what's in front of you and act on that instead of blindly (robotically) doing what the GPS wants you to do. On interstates and freeways, it's mostly good, but not always, either.