Mobryan said:
We do a lot of hiking/exploring away from the vehicle, if I can't get back to it, the stowed panel does no good.
If you hike, get lost and in trouble, and can't get back to your vehicle, finding the vehicle won't do you much good, either. Seems to me you would need the florescent panel with you, not on the roof of your truck.
Having done aerial search and rescue for many years back in the 80's, I find that cars and trucks are quite easy to spot from the air, and don't really need stand-out markers to be found. People on foot are another story. Even from 600 feet up, a pedestrian is almost invisible. What we found hardest to spot from the air was a wrecked airplane, mostly because they ended up in a shape that was not readily recognized as such. Unless you plan to roll your truck into a ball of junk, I don't really see a benefit to putting an orange panel on the roof. At best it would help a search team differentiate between your truck and someone else's, and then only from the air.