What issues are concerns for driving fatigue?
On mine, any fatigue above and beyond driving a car is due to the larger width and less precise handling than in a car coupled with urban driving conditions. It just takes more alertness and driver input than a car in congested conditions. The more brain inputs and resulting corrections I need to make, the more quickly I fatigue. I often adjust driving distances accordingly.
At least in my case, I was interested in the handling improvement threads. I try to get the tracking straight, and steering precision best possible.
On my motorhome noise, comfort, and ride quality are not issues.