Question about Leica M-Monochrome

Dear Leica folks,

I am new to this forum, just peeking over from Sigma, where I usually belong. I just have a question out of curiosity to which I could not find a quick answer right away. So please forgive me if I repeat it. The question is the following:

Is it possible to achieve all of the possible b&w results of the Leica MMonochrome with another Leica (say M9 with colours) by postprocessing the images?

Or to put it differently. Is there something one would miss out on (apart from convenience) having "only" an ordinary Leica compared to the Monochrome edition?

Thanks in advance,

Mattanja