Hi. I have been using one for a couple of months. To my eye, the lens is hard to fault in every aspect, i.e., sharpness, contrast, bokeh, etc. However, it lacks a strong character such as biting sharpness of Leica 50/1.4 asph. In this lens I am yet to see the signature I saw in Contax 50mm/f1.4 and 45mm/f2 Planars. Perhaps, I am hard pressed to tell any differences in images taken with the Planar and the current Summicrion. If you adore your Leica 28/2 asph, you may prefer Leica 50/1.4 asph.
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