Some users feel that the 50mm Summitar produces a particularly pleasant "Leica Glow".
For wide open sharpness, though, the LTM Summicrons will be the better performers. If wide open sharpness is most important to you, the current CV f1.5/50mm Nokton, by my testing, easily outperforms the vintage Leitz lenses.
Time to start a Leica LTM forumhere, IMHO (maybe we have done just that).
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