I have the MM3 and it is awesome!!
I highly recommend this mill. I have never owned any other mill, though.
I own MM-3 (owned for the last 5 years or maybe more), I bought hopper and base (because I am lazy) which holds over 10lbs of grain, and it is nice. I run it with a newer drill. I do wished I would have invested in the stainless rollers (but only just because I like stainless, and the mill has a little oxidation on the rollers, which doesn't affect its performance). I use factory settings (never changed), and have nice efficiency and no run off issues with my mash tun set up (keggle, stainless false bottom), even when I use 60% wheat.
I had trouble with crushing wheat but that was my old drill, new drill runs through it like butter. I would buy it again, but probably never will need another.