Recent reviews indicate that the lens is super sharp. I wonder if a 135mm lens is used for anything other than portraits, in which case you may not want extreme sharpness. Perhaps other characteristics - contrast, color, bokeh may be equally or more important. Frankly I've never been able to appreciate the 'character' of a lens, despite having owned Leica glass.
Interestingly, I was at a museum this weekend, saw some 'great' photos, most were blurry and would be trashed today. However, they are considered 'art'. So it all depends on what makes one happy I suppose. There was one particular exhibit which was basically a blue square, about three inches thick, in laquer. It was nothing but blue paint with a lighter slightly pink border, about 3 feet on each side. No idea what was so great about it, but it is still considered a great piece of art, to be put up in a major New York City museum.
Having said that, too much GAS these days, I may put in an order for one myself