Agreed about hull covers, they are indispensable for long-distance trailering. They are also good for off-season storage. I have a set of covers from Salty Dog, trailered over 3000 miles, no dings. And also sun damage is much reduced compared to uncovered boats of same vintage.
Don't expect the covers to keep the hulls *clean* when traileriing, unless it never rains on your trips. The spray from traffic during rainstorms will leave some fine debris between the covers & hulls after they dry. But the ding avoidance is excellent!.