The Voigtlaender/Voigtlander Lanthar SL 125 F2.5 is indeed a wonderful lens! To wit,
1) Virtually no aberrations/distortion
2) Does 1:1
3) Super sharp, starting at F2.5. I mean SHARP.
4) Creamy creamy bokeh. I mean CREAMY.
5) Impeccable metal construction
I bought mine just before it became no longer readily available. I regret not buying two!
I also happen to own a Kiron 105 F2.8. But it's been 15 years since I've used it. Time to dust it off and do some comparisons!
Here're some weekend shots, taken with the Lanthar in harsh sunlight, F2.8. The first:
"Portrait of a Man" by Louise Solecki Weir. Ceramic. [I need to lighten up the eyes/eye socket area.]
The second:
"Individustrialism" by Mario Armitano. Bronze.
This obligatory flower shot was taken a few weekends back, in direct sunlight, F3.5. Nice bokeh!