The C/V 50mm f:2.5 Color Skopar is 7 elements in 6 groups, not 4 as your note might be read to imply. If you read online user reports and comments, such as on the CVUG list (Cosina Voigtlander Users Group), the impression you'll get is that this is not one of the finest in the C/V lineup. The 50 f:1.5 Nokton gets much better reports. I haven't used the 50mm Color Skopar myself, so this is secondhand information, but compiled from a number of owners' and users' reports. I haven't read a single report saying the 50mm Color Skopar is a great lens. I do love my 75mm f:2.5 Color Skopar, which Erwin Puts claims is based on the Elcan (that's E. Leitz Canada) 75mm f:2.5. But I liked it even before I read that claim.
Originally Posted by David H. Bebbington
Also, I'm sure most people are aware that there are a few generations of 50mm Summicrons out there, not all of which perform exactly alike, so comments on one may not necessarily pertain to the other generations. I'm not enough of a collector or hardware nut to have memorized the exact details on this, but I'm sure you can find it online somewhere.