pictures look fine, nothing wrong with a summitar, although Leitz obviously thought there was so they made the Summicron.
I like to tell folks that some of the greatest images in the world, ever, were shot with uncoated optics and lenses that would be considered junk by modern standards -- really, what matters is the shooter, not the lens. And a few scratches won't hurt at all, although a lot can degrade the image. These older lenses have defects that do give them a distinct look, although that look often makes a more pleasing image.
I'd be embarrassed to admit how many of last year's really good shots were taken with a Holga, for example.
Since I've already bumbled once, I won't say anything about the comparisons of Leica owners and Holga lomographers...