A collapsible 50/2.0 Summicron came with the M3 I bought back in the mid-1990's. It's like most fast lenses of that era, a tad soft wide-open sharpening up nicely as you stop down. I really don't consider it to be a "special" lens and it doesn't give my pictures a "special" look. Actually, I rarely use it now, much preferring my LTM Canon 50/1.4 or my 50/2.0 LTM Nikkor.

Jim B.