That earlier post was a little overzealous. I did *barely* make it over 60 once, but rarely managed to get past 55 on the downhills. However, it was *completely* functional to drive on 281 and 290. I simply moved onto the should to let uphill traffic pass. Wrote down my odometer at the first fill up, so next fill up will start getting mileage data.
I had no idea what quality felt like until today.