In article <531gb1$41r@ayce.ayce.com>, Larry@ayce.ayce.com says...

>I have used both the old and new versions of these lenses. I had them
>resolution tested on an optical bench. The newer version had twice the
>resolution of the older version. The newer lens is also smaller then the
>older version. This makes the newer version much easer to use.

Hmmm, I have used several samples of the older version, and a couple of
the newer, and your observations sure surprise me! ;-) I found the older version sharper in use at medium-long to long distances. Since mirrors
appear to be distance sensitive for resolution, and since the newer
version allows very close focus, and since the newer version appears
(therefore?) to peak at considerably closer focus distance than the old, testing them at short distances might make the newer appear sharper than
the older version, but unless the older version sample you had was
defective, it seems unlikely that the one would have twice the resolution
of the other (which would make the newer version one wonderful lens,
since the older version is quite sharp - and sharp enough to look good
even on a 1.4X converter). Also, I find in practice that greater mass
and physical length actually help in getting sharp pictures with long
FL lenses.
Hope This Helps