Quote Originally Posted by TOM View Post
.... the only reason they don't include the ring, is to cut costs. ....
I would have thought weather sealing and a more reliable mechanism and manufacturing process would have been foremost in their minds, rather than saving a few dollars on a multi thousand dollar lens.

Where there is direct access from an external moving part of an item, to operate the inner workings of that item, would require a complicated sealing mechanism to inhibit the ingress of external 'elements'(dust/moisture/etc) into the inner casing. If the part is a moving, then there is also the chance for that part to wear out(highly unlikely, but not impossible). Aperture rings have been known to go stiff on various models of lenses, so problems with mechanical components such as these have been known to cause problems, as such.
AFAIK, I cannot remember any of the non G lenses to be fully weather sealed, as the G lenses can be(I'm sure someone will correct me on that one tho.. I just don't know of any)

I have both types as well, and find it annoying, like Andrew, that I can't access 1/3 stop aperture increments on my Ais lenses.

There are advantages in having an aperture ring tho ... these reasons are too few and a bit too technical to worry about(IMO).
For every G type lens that doesn't work on older film bodies, there are a zillion more Nikon or other types of lenses with aperture rings to mount onto legacy camera bodies such as F4's and suchlike, so I can't really see it as a problem personally.

FWIW, for the case where the lens won't work on a F4, it'd probably be prudent to seek out an F100 for the purpose of using these G lenses more effectively on an old film body(or F90/x, or F5.. or whatever).