I have used both makes of lenses and currently use a Nikkor 50mm F2.8. As far as I can remember the Rodenstock Rodagon 50mm F2.8 was about the same standard - that is both were/are damn good, but I may give the Rodenstock Rodagon a bit more credit when printing colour especially if it was the APO version. The Nikkor did seem however to have the better build quality.