I went with the MM2-2.0 model with hardened steel rollers (last longer than the other rollers by leaps and bounds) and couldn't be happier. I also opted for the base, hopper, and hopper extension from Monster at the same time (ordered direct). The entire thing is built like a tank. I use my 18v DeWalt cordless drill (1/2" chuck) to run it. With a 39# hopper capacity, there's no way you'll want to hand crank it. Customer service/support from Fred is top notch too.
I had a BC before this and it's a toy when compared with my Monster mill. The C&S my brew buddy has also looks small when you put them side by side.
I reviewed tons of posts by corona mill users before getting my first mill. All the crud they needed to do to get the mill adjusted so that it would crush properly was too much work IMO. Plus, the tiny hoppers included (even when you ordered a larger one it only held a few pounds) was ridiculous... The BC I used for some months did a decent job, but neither the corona or BC are in the same class as the Monster mills. It's like the difference of tether-ball to MLB...
If you go with the 2" diameter rollers with the Monster mill, I don't see you ever regretting it. Get the hardened steel option and your great grandchildren will be using it to brew after the alien invasion is over.
