He did not give any info what or why etc... unless I missed something.
My geuss though is a travel trailer/camper going NY to AZ on summer vacation.
Weight and other things would not be a factor if so is the case since the panels need hauled anyway for the desert camping trip rather in use or not durring the drive.
If mounted flat to a roof in a safe manor in direct sun I think all should be fine and provide however much power they make while using no extra feul to do so. The vehicle alernator would use some feul to make same power the panels would make for free. Having hauled and charged L16P trojans (360amphr batteries) plus others in my P/U truck I dought the alternator would be using all that much extra feul though to equal a few panels.
I have thought of mounting my 36watt panel on my little motorhome roof for the same reason. It has to be hauled to be there when I get there, and it might as well be making power on the way since I will stop many times and be using that power durrng the drive.
So far I haven't used the motorhome since I got it home last year.
Excess wind speeds over a moving vehicle is my concern but should be doable. If driving 70mph into a 30mph head wind, that is 100mph winds over the solar panel!!
I probably would not do that in a motorhome or towing a large trailer, but 50-60mph driving is normal and you gotta watch out for those sudden gusts of wind!!