Some of the main differences being that the axles are made out of brass tubing and the end caps are made metal as well. The use of my Dremel workstation also made it quick to drill the holes into the body of the train. This means more uniform looking pieces at a faster pace.
I think I'm getting close to a final prototype. The main thing now is to take this prototype and find the right "custom train" to put on top to make this the thing people want. Right now it sitting empty makes a cool concept, but nothing more. Nothing worth funding anyway.