Hi Gary. I made a decision for my own work to rely on:I hear you Harry, but I don't buy it.
I've had 4 RVs all wired with Romex and never had a solid wire failure -- a couple of them had quite high mileage with lots of rough roads.
Many (most?) commercial RVs are wired with Romex -- I just don't see them taking the legal risk of doing this if there was any real problem.
The low freq vibrations you get driving an RV over roads just don't seem to me to be the kind of vibration environment that would cause wire failure.
I spent some time searching for actual reported instances where people reported real failures of solid wired in RVs -- I could not find any.
I could be wrong, but just don't see it as a real issue. I'd like to see some hard evidence.
- Data sheets
- Known good practice
- Electrical code (as much as possible)
- Asking experts
If I spent a little too much on components and ended up with very low failure rates, I am happy with that.
For the short wire lengths in a van, it isn't worth while for me to consider that I might be smarter than ABYC guidelines and the wire data sheets and shave off a few bucks in wiring.
The wire that I suggested is relatively inexpensive and widely available. I wouldn't wire a house with it, but a van - sure.
I know that you are looking for hard data and I am not in a position to supply it. I actually enjoy pushing on what can be done in a van electrical system but I have just chosen to be conservative about wire application guidelines.