If you don't understand the need for the Leica M-Monochrom then there's no need to buy one. It's not about the technical capabilities but about the psychological effect on the brain when composing using a camera that's only able to capture a B&W image (in exactly the same way you're forced to think about tonality when you load an Leica M6 with Tri-X or FP4 Plus). For me personally, the M-Monochrom is more compelling than the regular M9 but, as they say, 'your mileage may vary'.
No one has seemed to mention the fact that adding red, blue, yellow or green filters to the lens will decrease the sensor's sensitivity, effectively giving up some of the gains of removing the array in the first place. The B+W Red 091 Filter, for instance, has a filter factor of 8 (3-stops). What's more, few commentators, if any, have mentioned the M-Monochrom's IR cut-off filter (it doesn't use a OLPF). There are generally two types available; absorptive or reflective (short pass interference). It's most likely the M-M uses a thin absorptive type, but either are a shortcoming. I wonder why they did that. Oh well, that's why there are reviewers I guess.
What do you think, is there a case for the Monochrom?