[ascagnel_]

I find GPS most useful if I already know the route -- it can give me advance notice of traffic out of my vision, or it can tell me which of two routes will be faster (an example is picking either the car or truck lanes, or east or west spur of the NJ Turnpike, which has multiple mostly-parallel routes).

In cases where I don't know where I'm going, I try to set any GPS app to keep to freeways and arterial roads when possible, since those tend to signed the best.