We taken ours down some pretty rough roads including the Historic Route 66, the Top of the World Highway (specifically the section from Chicken, AK to the Alaskan Highway) and the gravel highway to Wood Buffalo National Park in the Northwest Territories of northern Canada. Though each of these was rough, they may not have been as rough as some long washboard road construction areas. The trick to driving these is simply to match your speed to the road conditions. This is sometimes difficult on really bad washboard as almost any speed seems to fast. We once did 13 miles of washboard at about 10 miles per hour. Also, watch the road well ahead to make sure you are nor caught by severe potholes.
The one type of rough road I try very hard to avoid is uneven, rutted roads that will twist the frame and body of the coach. Twisting is not good at any speed.
Retired and livin' the RV dream!
2005 Newmar 43 ft. MADP, Cummins ISL 400HP, 2018 Jeep Wrangler JLU Sahara