I have owned my 200MM Medical Nikkor for 40 years. Used properly, it surpasses most, if not all, of today's macro lenses, two of which I have, and choose not use.
You can't compare 1960 technology with that of today's optics. It is not intended to focus to infinity; in fact, there is no focusing. If it were being hand-held (as in operating rooms), the ring-light won't be effective much beyond 1 or 2 metres.
Focusing is achieved, by moving the entire lens. In my case, I use a focusing rail, with a Nikon F film body mounted on a Miranda copy stand.
I photo-document coin and stamp collections for insurance companies, and they have unanimously endorsed my system. Images were* crisp and sharp, with excellent colour rendition. My clients now demand my material in digital form, So I have been converting slides to digital, with a slight *loss of resolution, but worse, suffering an excessively long time to get my slides processed.
Because the Medical Nikkor is at the heart of my business, I have now converted to an Olympus body. with an inexpensive adapter (it all boiled down to a body that would fit the camera bracket of the stand mounting). The whole process was already totally manual, so I have not yet experienced any new problems; and finally bypassing the baulky and expensive process of converting images.
For reasons purely of quality, the Medical-Nikor continues to be my lens of choice for this app, and I will use it 'till I stop working.
Incidentally, for those owners of the early (Series I, 4-pin) lens, and unfortunate enough to have only the DC power pack, the 250 volt battery has not been available for quite a few years, and the AC power pack is the only alternative. The lens will not function without an external power supply.
Gord Clark