Nice Big Dummy Chris.
I built mine up with a SRAM X9 rear derailleur because of the stronger return spring. With this spring there is no need for a frame cover to protect from the chain slap.
I used Schwalbe Big Apple tires 2.35 for the best load rating (160kg) I could find. Also the built in tire suspension works amazingly well.
For stopping power, I used Avid BB7 disc brakes front and rear. When it’s wet and loaded I want to stop like now, if needed!
I love my Big Dummy. But my build cost me around $2,300, so I’m not too comfortable leaving it locked up outside the grocery store.
-O-^O