I've always been amazed at the overall image from a Holga or Diana, I think part of it is the fact it's 120 film. They give a soft focus but the grain is not so pronounced because of the film size.
These "crappy cameras" are great for getting images you can't from razor sharp Canon, Leica, Nikon or Zeiss lenses and the entry price is affordable.
I like folders for the same reasons.