Rust Repair

Rust repair, any ideas? I've seen both, ADM Goodmark advertised and they both look like original pieces on shape and contour, there's quit a difference in costs. I've seen ADM's add about weight versus the competition, I am assuming that this versus Goodmark, I could be wrong. And I know that in the end the price difference will be insignificant, but just would like to hear from those that have used one, or the other.

67 Dart versus Valiant repair pieces? There is a lot more available repair pieces out there for Darts rather than my Valiant. Are there any/many differences, really? They're both A-Bodies from the late 60's? These are things that I've noticed since I've found a few rusted out areas of my new project.