I've never owned a vehicle with Nav before. I ordered it on my new rig mainly because I liked the big display and the Nav seems like a neat toy. Unless I change careers and start delivering pizzas, at this point it doesn't seem that "practical". I'm looking forward to getting it, but I wonder. Is it a novelty that wears off after a few months, or is it more appreciated with time? I realize everyone's situation is different, but am curious if people really use there nav like they thought they would six months or year down the road.