LOL...You mean the 135mm DC I sold a few months ago at approx. half that price (here on Getdpi) was too cheap? Hey, how do I apply for a refund
Seriously though, these lenses are both unique but often somewhat fustrating for some users. As a stand alone 105 or 135mm (without using the DC function), they are generally superb as portrait lenses, warm and inviting, sharp and actually fall more into the Zeiss/Leica catagory in that they have character in the way they "draw". Before the days of being able to digitally post process, the DC lenses were much prefered to the Nikon 85mm f1.4 for portrait work.
Here is the somewhat fustrating part for new uers of these lenses. The DC control introduces spherical aberation "SA" (along of course with shifting the focus point). When using MF, most of these aquire the sharpest shot when DC is set to "0". When using AF though, many samples (set at Nikon) actually achieve sharpest image when the DC control is set to "F(front) 2". It also depends if one focuses first, locks in focus and then turns DC seting...OR focuses, turns DC ring and then re-focuses. Results in these two cases are quite different since once SA is introduced, the focus point shifts. With the ability to adjust Af in many DSLR bodies, some set the DC control to "0" and then with using Af, adjust their DSLR to get shapest image when DC control is set to "0" (requires quite a bit of correction).
I also have a quite rare and wonderful much older Tamrom 70-150 f2.8 MF regular/Soft focus zoom, a lens few have ever seen or heard of and the literature that came with it, acutally did a better job explaining the workings of a lens that introduces SA for the purpose of defocus control, than even the Nikon literature...and that lens predated the DC lenses...although they are slightly different in concept.
It takes time to master and utilize the DC control but of course with digital, instant feedback is possible. Many though just use the lens at it's best (sharpest) setting as a fast excellent lens. Again keep in mind, the eye through the viewfinder doesn't see small amount of SA being introduced by this lens, and therefore when comparing MF vs. Af, will often get different results as explained above.
Dave (D&A)