PDR on Old Metal?

A friend of mine has a PDR shop and is very good at it, he says old metal can definitely be PDR'd, just takes a little more effort because it is heavier/thicker. Not every ding can be fixed mind you, its like @junkyardhero said, there doesnt appear to be any hard creases in it, which is a plus, and definitely go to someone reputable whos been around for awhile, its amazing how many pdr shops will "spring up" during storm season.
@BrianT said it right