I waited 8 months to receive the Nikon/Canon adapter from Mark Welsh, after placing my order in February this year. That's almost the time of the gestation period of the human foetus, so one might consider this adapter to be a premature baby.
I had a bit of trouble fitting the adapter to the Nikkor lens because a couple of miniscule screws had to be turned which I couldn't see with my normal reading glasses. I had to fit a jewelers' magnifying glass to my forehead and then locate a screwdriver small enough to fit.
The lens does not autofocus, understandably, but autoexposure does work in aperture prioroity mode. Unfortunately, selection of aperture is mostly guesswork. There are 3 marks on the adapter which signify F2.8, F8 and F16. The lens turns on the adapter across these marks, but there's no EXIF information in ACR regarding aperture, just shutter speed and ISO.
Another quirky thing which is a bit worrying is the inability of the camera to be completely switched off when the Nikkor lens is attached. The red 'activity' light on the 5D continues to flash at a rate of about one flash every 1.5 seconds, as though to indicate that a foreign object is attached to the camera and that something may be wrong.
I imagine that maybe the battery would run flat if the camera was unused for a few weeks.
I intend to compare this lens with my Sigma 15-30 and examine corner resolution. But I haven't got around to this, yet. However, this morning I had to arise early to take my partner to the airport, and for the first time in a long time, saw the sun rise over the Brisbane river as I was brewing my morning coffee. (I usually get to bed late as a result of trying to communicate with strangers on the other side of the globe.)
I grabbed my 5D with Nikkor lens already attached, and took the following shot, directly into the rising sun. I'm very impressed with the absence of flare. A shot like this with the Sigma would have produced great elliptical blobs of red.
I don't see any significant signs of flare in this shot. Do you?
14mm, 1/125th, ISO 100.