I recently went into Best Buy and there was a working Dezl on display. I set it to RV mode and entered all the vitals and then it asked to take truck routes and I did not check this box. I had it route to a location that could go through low overpass limited access highways or through a highway with no clearance problems at all - it went the route that would have torn the roof off an RV with the height entered into it. The truck route box had to be checked in the RV profile to have it go the safe way for an RV - but this followed routes for commercial trucks which was the longer way to go and not an RV route that would be shorter. If you are considering the Dezl go to a retail store that has it and try before you buy to make sure it takes you on correct RV routes.