I opted for the 50/1.8. It is a really nice lens, tho I haven't tried the 1.4 versions (I most likely will not get it). I am pretty happy with the results from it. Sharpness, rendering of the OOF areas and color rendition is just right for me. This is a shot from the 50/1.8 wide open ( mine is not the MiJ version).

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