I drive 79 from Pittsburgh to Erie and back most summer weekends. About 135 miles. There are cops in a few predictable areas, although not many. Speed limit is 70, most people do between 70 and 80, a few push 85 mph. Pretty safe, for the most part.
People still use those? The were very popular in the late 80’s, but I haven’t seen one in forever. Waze is my friend.