I came up the northern end of it yesterday ( oppenau to baden-baden) it’s still a good road with cracking views regardless of speed limits. It just gives you more time to enjoy the scenery.
Latest speed limits give you time to do a decent oil painting of the scenery, was there last week but pissing with rain so I got to the Hotel pronto and dodged it, my mate rode it anyway and seemed to enjoy himself, but I very much doubt he paid any attention to the posted limits, which sums up the entire trip.....
...Ride to your limits and what you can afford in the way of tourist tax from the cameras, and in fairness there aren't many roads that are heavily policed and covered in cameras, and plenty of good stuff away from the B500, travelled along several 10+ mile stretches on our way there that were every bit as good, but without the plod / low limits factor (Ardennes, Luxembourg, Eifel)
And if a ticket turns up it was well worth the price to not constantly worry about the speed / fines, one day we will all be electronically castrated so enjoy what little freedom you have left.