This may not be the right place for this post. If not I apologize. I was on google plus and mentioned it would be nice to have an inexpensive 35mm prime for an FX Nikon. Someone responded and said you could use the 35mm 1.8 and vignetting was not bad. I tried it and was impressed. You have to take your D600 out of auto DX mode. Anyone with this lens should try before selling all your DX gear. I did a test shot in my library. I cropped the corners 1:1 for review and just below center. While the corners are not perfect they are pretty good and not bad compared to some of my FX glass. I shot it at 3.5 1.3 sec iso 100 on a tripod. I shot a couple portraits and found the vignetting could also be at least partially corrected easily with Lightroom.
"Cameras and lenses are simply tools to place our unique vision on film. Concentrate on equipment and you'll take technically good photographs. Concentrate on seeing the light's magic colors and your images will stir the soul." Jack Dykinga