Duplicolor SHIELD isn't as protective as a clear-bra application or a clip-on synthetic-bra, but it does protect to a reasonable & respectable degree. If aesthetics aren't of concern while traveling, multiple coats can be applied to increase the protection. Sizable rocks/pebbles/debris will penetrate single-layer applications, but double-layers can weather them relatively well. I've never personally applied more than two layers, but if done correctly & in the right conditions, it's possible & plausibly the protection should be accordingly augmented. . .
Reference:
(currently offered in clear & black, and can be found in gray as well (limited leftover quantities from the past)
Another alternative would be to get a cheap'o heat-gun from Harbor Freight for ~$10'ish (blow-dryer's can work as well, I believe) & left-over roll of vinyl on clearance @ a specialty shop (likely cost will be less than 3-4 rolls of painter's tape or 2 cans of spray-shield bra, etc') & make your own custom 'road-trip'/convoy bra or front-clip shield. I did that quite awhile back when I was w/ a friend & we were trailering his car w/ a hitch on an S.U.V. It's very analogous to how brand-new vehicles are protected while being transported to dealers aboard 18-wheelers or on freight-trains. For less than ~$20, the entire front-clip was covered w/ enough material left-over to do another 2 applications (obviously depends on how much vinyl was purchased). . .
G'luck w/ the trip. Mebbe' us Austinites will coordinate a drive, as the last Sunday of every month, we've set aside for meet-&-greets along w/ a drive to be followed by brunch/lunch/etc'. . .
, if you do use it, be sure to go with brand new tape and take it off asap. It breaks down (especially quickly in heat)and the adhesive stays behind. It's a big mess.
