Hello,
the exchange of the front window really did improve the flare of my M 6 but on the other side now the LED's are too bright. If you follow the development from the M 3 to the MP or M 7 you cannot say that Leica was really innovative. The M 6 had the technical niveau of a Pentax Spotmatic from 1964. They did not invest huge sums into the improvement of a design that with the M 3 in 1954 was so perfect.