Going south, it all depends on your right seat passenger's tolerance for being on the edge of the cliff! My wife would much rather go over the North Cascades on SR-20, because the cliffs above the road are on her side. She's a lot more nervous on US-2 because the cliffs down from the highway to the Wenatchee river are on her side.
We've done part of the Oregon coast both ways and did it from top to bottom this year. On the whole, the road isn't too close to the sheer drops, and not having to turn across the southbound traffic is a plus.