i do some comparison for Voigtlander 40/1.4 ($ 529) vs Summilix 50/1.4 ($ 3995)
Setting is about the same iso 320 f/2 and 1/20 sec, both picture still is not edited (retouch)
this picture taken with summilux
this picture taken using Voigtlander 40/1.4