The warnings had kept me away. Then a friend who'd been there said, "It's not that bad. Just air down your tires to smooth out the washboard, and watch for the bigger potholes." His encouragement, plus reading House of Rain, made me want to go. Now.
The good news: the first third of the road from US 550 is paved. No sweat.
The okay news: the middle third is fairly well maintained gravel. Some mild washboard, but if you cruise at about 40 MPH so you're skimming the tops, it's not bad at all.
The I-guess-it-could-be-worse news: the final third, before reaching the park and its pavement, is like this.
And then there are patches like this.
The sign at the start of this section of road should say, "End of ANY maintenance at all."