The Holga and the new Diana are different at least the results I get from my examples. The Holga has less spherical aberrations than the Diana personally I prefer the look of the Holga for most pictures. The Old Diana again has a different look than both the new Diana and the Holga. The older Diana has stronger spherical aberrations than the Holga but less than the new Diana, the image is somewhat softer than the Holga's but not by much. I like the Holga and old Diana equally well but the results I get from the new Diana are often too harsh (sharp, contrasty, too much aberrations). Everything I just wrote was from personal experience with the cameras I own, results might differ from other cameras by the same manufacturers. BTW Holga has solved the problems with the aperture and now offers f8 and f11. A point in favor for the new Diana is the Pinhole aperture.

Dominik