I know "bokeh" is rarely a prime concern in choosing an enlarger lens but I plan to put it to double use. Recently, I took my Voss 50mm/f3.5 generic enlarger lens for a spin as a macro lens on my F3 and I really liked how compact and usable it was. I never did like the images from my 50mm/1.4 lens when used reversed, so I think a quality flat field enlarging lens might be a big step up.

So, when it's not doing duty on the enlarger, I plan to use it reversed on extension tubes for 2x to about 6x magnifications and hence the bokeh is a big concern for me. I recently saw a picture of a Schneider 50mm which had an almost square aperture!! - that has got to produce sime pretty harsh OOF renditions. So among the usual suspects - El-Nikkor, Schneider, Rodenstock - which 6 element lens has the most number and the most rounded aperture blades? If anyone has experience using them as macro lenses, I'd love to hear your thoughts as well.

I'd love something fast because I might need to use it wide open at high magnifications to avoid diffraction. I am also aware that OOF renditions are affected by more than the shape and number of the blades but all else being equal I suppose a rounded one is much better than a square one, so any insight, recommendations and caveats on that front would be really appreciated.