Thanks Jakov, Rob, Airy, Tom and Sten.
There is still no real compare-test between the two 58/1.4 lenses. The Voigtländer is already sharp wide open (very sharp for a fast lens) I love the lens for it's size, versatility and built quality. It sometimes 'wild bokeh', which I like and gives extra possibilities, can be controlled but is a point of attention. The only real drawback I can think of is the 58mm filter thread which is unusual, it makes the use of close-up lens difficult or are there converters from 58 to 52mm?