Wow, cool to see this thread resurrected.
I bought my M Monochrom in early 2013 or perhaps late 2012, and then had the sensor misadventures in early 2016.
The camera went to Leica New Jersey and after waiting 10 months, was returned with a description that there were oil spots cleaned from the sensor, but no corrosion.
Well, there was corrosion, it went right back the following week and eight months after that I was informed that it would be about 6 more months for another sensor. I argued with the management in NJ about how I should be at the very front of the queue because of their previous 10 months possession of my camera, and after receiving "no promises" of faster service I took the step of sending Dr. Kaufmann a private message through FaceBook. Two days later and I had a brand-new M Monochrom.
I used the new camera for a few months and then it got jostled fairly hard and the rangefinder was knocked out of alignment. I sent it to New Jersey (big mistake) and four months later it came back to me, horizontally aligned, but still off vertically. I traded it in towards a new M10 as I just didn't want to deal with it anymore.
The M10 was lovely. I also traded in my M-D (the one with no screen, itself an upgrade from my M-E (new sensor in 2015, but with old style cover glass). The M10 was, if anything, too good. With the EVF attached it felt more like using a Sony, and without the EVF it was like using the M-D, only thinner, with worse ergonomics (I loved the M-D ISO dial, hated the M10's) and files that if anything were too perfect.
A few months ago I downgraded to another M Monochrom (with the updated coverglass on the CCD and only about 1,000 actuations) and another M-D, which is just so much fun to use without an LCD. I also downgraded from mostly modern Leica glass to vintage, and only have two modern lenses for when perfection is preferable to character (Zeiss 35mm f/1.4 Distagon ZM and Voigtlander 50mm f/1.5 Nokton ASPH), otherwise I'm far more likely to use my ancient 1937 Sonnar (thanks Brian) or cheap though lovely Voigtlander 35mm f/1.4 Nokton SC.
I must say it is SOOOOOOO good to be back to the M Monochrom. This has got to be my all-time favorite camera.
Here is an image from 2013 with my first M Monochrom and the 1937 CZJ 5cm f/1.5 Sonnar (coded as a Summilux)
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