Incredibly good! Go ahead and buy it, there's nothing even close to these specs other than the new Leica 35 Summicron APO. Tested on M10 and M10M. Lenses compared to (and they lose when edge sharpness and color fringing are the only criteria): Summicron ASPH vIIDistagon 35/1.4 Ultron 35/1.7
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