I've been copying this design verbatim, especially the hopper. I ordered the MM3 (not the 2" rollers) and added a power switch and reverse switch as well.
But man, that hopper's killing me! I'm trying to bring my sloped edges all the way to the top, and while the longer ones (the normal rectangular ones on the ends) aren't an issue, I'm having a helluva time getting the trapezoid ones to fit properly. Grr!