Keep shooting and enjoying Vladimir!
There is a unique quality to this lens that several members of the old Leica forum talked about, but which is seldom mentioned elsewhere. If you shoot very, very low-light scenes (1/8s or longer, wide open), you will often find the resultant image has a tendency to scan and/or print brighter than you remember the scene being (and brighter than if shot with another lens with same exposure values). I have encountered this several times, when I had expected the image to be dim and murky. I recall someone on the old Leica forum saying it was as if the lens "had the ability to make light where there was none"