I've done all of those multiple times in our 40' Endeavor towing our Wrangler. No real issues on any of those roads. Yes, there are some relatively steep grades but nothing to get your panties in a wad about. Only real comments are on 128 and 12. 128 is a bit narrow and twisty along the river. Mostly depends on the idiot coming the opposite driving way too fast. There has been much discussion and debate about 12. Lots of white knuckled reports and never again statements on this forum. Yes, there are some places where you could drive off the edge and make an ugly splat way down below, but the views are worth it. I would rather drive 12 than 128 in my bus. I've even been known to go out of my way to drive 12 between Torrey and Escalante.