My July Nikon Rf months is still going strong - I only got started on July 7th so I figured out that I had some extra time left. So far about 300 shots posted on Flickr with a variety of lenses - from old to the latest - and at the moment I am getting into some Zeiss glass (21f4.5 Biogon and 35f3.5 Planar) as well as some VC lenses.
My conclusion is the usual. If you shoot mainly black/white - it makes virtually no difference if you use a 1957 lens, or even a 1950 lens versus the 2000 Millennium 50 or the SP 2005's 35f1.8. Nikon got it right early on and improvements were more incremental than substantial changes. Out of approx. 20 lenses used so far - only one has shown signs of acting up. A chrome 50f2 is giving me problems with a weird focus shift. I will stick it on a tripod and shoot some "measured" distance tests just to check that it is not my fault and not the lens.
Still have a plethora of lenses to use (25f4, my 2nd 28f3.5, 105f2.5 and the 105f4, the 135f3.5 - two or three of these and another two 85f2's - and of course the full gamut of VC lenses!) Might have to extend the July way into August for this. Oh, there are some Jupiters to to try out.
At least the weather has turned summer like and that helps.