Front bras have a tendency to lodge dust underneath which rubs on the paint.
Rear flaps have been known to kick up rocks on the toad.
We only used the stiff mud flaps behind the tires and got no toad damage... even for the drive to Alaska. We saw others in Alaska actually removing the big across-the-RV flap & they pointed out a layer of rocks at the base of their toad's windshield, along with scratches. We had absolutely no damage on the toad or motorhome - in 8 yr. of using it during full-timing. We traveled many gravel roads because we love boondocking.
Since your RV is small it might be manageable to put on an all-over cover - they can be unruly on a big RV. However, they can still rub during winds on the paint job.
I'd go with the tire mud flaps and good waxings.
Full-timed for 16 Years . . .
Traveled 8 yr in a 2004 Newmar Dutch Star 40' Diesel
& 8 yr in a 33' Travel Supreme 5th wheel