Mary, I had deja vu on your cruise control question...sorry sm, I agree with Karl on this one, anywhere but flat highway cruise is not as efficient.

I've driven in Ireland, Spain and France (on the Superhighway). IMO, overall European drivers are much better than American drivers. On the superhighway differences in speed of various vehicles were marked (guessing up to 30 mph). It didn't take long to figure out you had better pay attention if you wanted to use the left (passing) lane. Turn indicators and headlights are used extensively for signaling the other drivers of intentions. They use the passing lane just for that and get right back over in the right lane, and do it ONLY when passing will not impede (slow down) the progress the faster, overtaking cars from behind. Works great once you know "the rules" and everyone seems to abide by them. I've never seen anything like this on US interstates. How many times have you encountered one car (with cruise on) going 72 that's passing another car (with cruise on) that's going 71?