I have always enjoyed this woodchip hopper car type. Finally got an N scale version via Bone Valley Models at Shapeways. Bought this kit some time back, finally got it completed. Gold Medal Models ladders, Circus City Decals. I'm happy with the results.
I used pinewood derby car weights that were round, cut them to fit the width of the hopper bays. Then cut them in half to make half circles and glued them in place. Very low center of gravity and the car tracks wonderfully.
https://www.shapeways.com/product/E6EDC6VZZ/n-wood-chip-hopper-70-6-pack?optionId=10341738 I also have several kits I won't be assembling, I have enough cars if you want them let me know.