Hi there Monochrom "guys" - may I ask you longterm users - do you feel a tonality difference vs converted color images from M10(r) or M11 ... or is it mainly noise difference in higher ISO ...or the mindset to shoot a b&w camera or anything else make you use and enjoy the Monochrome Leicas?
I use my color M and allways try to tell myself, that I can alllways convert to b&w and that I dont need a B&W only camera.
I've been doing B&W rendering from color raw files with dozens of cameras since 2003 (the year I bought my first raw capable camera). The only color camera with which I can get results comparable to the M10-M is the Hasselblad 907x ... and the difference between these two and the rest of the cameras I've used is the fine-grained texture of the image coupled with extraordinary dynamic range.
I spent some time comparing the M10-M and M10-R recently. The difference in dynamic range and detail retention is quite obvious when you do a side-by-side test of the same test targets under the same lighting, never mind that the M10-M can return a nearly noise free image at ISO settings of 50,000 where the M10-R gets a touch 'rough' at 12,500.
Since I do tend to make mostly B&W photographs, I'd wanted a Monochrom since the M246 came out. The first thing I did was to make some shots of an Xrite Color Checker with my Leica CL and use my self-made B&W rendering presets on it to obtain a set of images which showed what I was looking for in terms of the color to grayscale translation. I then shot the Color Checker with no filter and a set of filters, and I found that the green and orange filters affected the translation of the Color Checker in the way that my preferred presets did. So the effect of using a green or orange filter nets essentially the same tonalities I was happy with from my previous color-raw to B&W work ... But with the M10-M's extraordinary image detailing, dynamic range, and ISO capabilities.
You might ask why I use the M10-M when I have the Hasselblad 907x and it can return similar qualities. Simple answers: I prefer the rangefinder; the M is a much more compact and handy camera that suits what I do now better than the Hasselblad; and keeping everything in my camera kit to one set of lenses allows me to learn the lenses better and better as I shoot more and more photos with the same lens kit. (I bought the M10-R so as to have a color option as well, now that I'm set on this strategy.)