I prefer AI-s lenses. I guess the main (and probably only) reason is that it is practical to put some boundaries when you are collecting something. I want to use the lenses on different bodies, including digital, so it had to be AI or AI-s.
I now have the following AI-s lenses:
28/2.8 AI-s crc - very cool because of it's biting sharpness and the close focusing distance
50/1.2 AI-s - not as sharp as modern lenses, but the out-of-focus areas have a certina very cool look
105/2.5 AI-s - very sharp and beautiful out-of-focus areas
Use use these lenses on a Nikon FE, Nikon FA, Nikon F4 and Nikon F100. I used to have a Nikon D700 and am thinking about getting a D750 or D810.
Cheers,
Jonas