Hey Mike,
Being a film guy I was never satisfied with B&W digital until the MM. I had a couple of semesters of the zone system while in college (yeah I did all the tests) and I printed all of my own B&W work (still do) and also, for a lot of years, did custom B&W and color printing.
I do have both LR and SE but I never warmed up to either. (Both came with the MM)
I start in raw and do basic adjustments there like contrast, sometimes correct perspective, density the usual basic adjustments. Save as tiff and then I fine tune in CS6. I actually use raw and CS6 a lot like I would work in a wet darkroom. I then make choices of what i am going to print and then I make a test print and make final adjustments from that print. As we all know a back lit image on a screen can look different from a print.
I noticed about 6 years ago I was seeing things n B&W. Shapes, tones etc. images that even though I shot in color were really B&W images. When the MM was introduced I thought that this was the perfect camera for me and my personal work so I went on the waiting list. I have had the camera now for almost three years and it was the perfect tool for the way I am now seeing.
It's like putting a roll of B&W in your camera. You are now looking for and shooting images that are B&W. It's not B&W as an after thought or maybe I can fix this bad color image in LR and SE. There is a purity to the process.
I am a full time commercial/advertising photographer and have been doing this full time since graduating from college in 1986 so my photography pays for all of my equipment. Yeah it is expensive but no more so that top of the line Canon and Nikon equipment and a lot less that digital Phase and Blad stuff. I can see where this stuff can be a stretch for a hobbyist though.