[Leica] M and R wide angle lens differences

[milos@bohem-net.cz (Milos Kocman)]

Responding to original post by Alfred Breull..

I was surprised to find that some M wide angles are judged by you as
inferior to their R counterparts. I guess that I have fallen prey to
Leica's slogan "Up to the limit of the technically possible" or what it is.
If this was true, shouldn't non-retrofocus lens designs always yield better
results?

I am particularly interested in the 2,8/28, my favorite focal length. I was
almost decided to trade all my Nikon plastic gear for a M6 with this lens -
should I have second thoughts now? Also, I've heard in the past that some M
lenses have the same design as their R counterparts - this would explain
why the M 28 is so bulky compared to the 35/2 - even if it's a stop slower.
Yet, the protruding back element would suggest that it is not a retrofocus
lens after all.

I would be grateful if anyone could shed some light on this.

Thanks,

Milos Kocman
milos@bohem-net.cz