This is my first post to a forum. I can’t resist this topic.
  When I head that Leica would come out with a 35 Lux ASPH that can actually focus on my 8.2, I sold the Lux and got on the waiting list for the new lens. I bought a Summicron-C to hold me over until the new lens would arrive. I love the Summicron-C so much, I bought a second one and an M-Rokkor too (At least my M-Rokkor example is not as well made as the Leitz versions, but optically identical). The Summicron-C is my favorite lens of all time. I love the weird bubbly bokeh and sharpness. I've canceled my order for the new 35 Lux ASPH.     
I have a 50 CV finder on my M8.2 to use if I want to see the actual frame and a 40 CV finder to use if my M9 will ever arrive. I hope CV will make a 40mm version of their metal finder. The 28 metal CV finder I use with the 21/4 Skopar on the 8.2 is much better than Leica’s finder (I have one of those too). I’ve found that Heliopan filters work perfectly (and better than BW, Leica) with the weird threads on the Summicron-C. 
The other nice thing I personally like about a 40mm lens with 50mm frame lines in the viewfinder is that the frame lines show where the subject should be in a 3x3 grid. Because of this, I now prefer 40mm over any other focal length. I feel a bit like I’m back to the days of my TLRs with respect to this grid-like relative frame lines property. 
  I have a CV 40/1.4 and I do not like it as much. To me, it has less character than the Summicron-C. I do also have a CV 50/2.0 Heliar which I love and which yields wonderful, surreal character. If you like lenses with character like the Summicron-C, you will like the Heliar too.    
  All the lenses I have owned:        
  M
90/4.0 Macro-Elmar-M    
  90/2.0 Summicron Pre-ASPH
  50/2.8 Elmar-M
  50/1.0 Noctilux (Canada)
40/2.0 Summicron-C (2)   
  40/2.0 M-Rokkor
  40/1.4 CV Nokton Classic 
  35/1.4 Summilux ASPH
  24/2.8 Elmarit-M ASPH
21/4.0 CV Skopar   
  16-18-21/4.0 WATE ASPH
  LTM    
50/2.0 CV Heliar   
  50/2.8 Elmar
  50/3.5 Nickel Elmar
  35/3.5 Summaron
  All the lenses I actually use:    
90/4.0 Macro-Elmar-M    
40/2.0 Summicron-C (2)
21/4.0 CV Skopar[FONT="]
50/2.0 CV Heliar
 
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