The peel-and-stick has a lot of appeal:
water proof
UV sunlight safe,
finished surface (no further paint, sealing, etc),
choice of color,
aluminum exterior,
wide width (36 inches) and overlaps easily.
Might be good for some, but not for me because
too heavy for a skin with no structural value other than resistance to penetration,
a little expensive for just a skin,
and I suspect it is not compatible with foam.
Perhaps someone with first hand experience can ring in on this.
As I recall, the guy who put a Pickup Cap on a trailer he pulled with a Scion (maybe I can find a link) used a peel and stick product (without the metal finish??) for the under coat of his floor.