there is a reason it has slanted nose, that is NOT just to be pretty
also when used when moving air flow is over the top and around the side side nose to back and draw heats from the coil
putting it sideways turns it into an air dam
disrupted air flow, may not be efficient enough to do what you want, cool the rv while driving
you ask for opinions, most don't think its a good idea
if this was primarily for stationary use, i would say go for it
it just may not work out so well while moving
putting it broadside is going to produce more wind resistance and possible problems with vibration and the mounts / clamping bolts holding tight