In my opinion, (and I am new to welding) it's not so much the welds (even if I would have grinded them) as is the location and choise of patcharea, the wheelhouse one is right over a seam, and its welded over the cutout, so it creates a rustpocket on the other side. The torquebox is a crooked patch in the middle, with a big rusthole above it, why not make it straight to the edge.... The third one has some bad welding I think, and no one bothered to drill the holes for the heatshield...