These cars are a good deal and result in a nice looking car when finished. I operate my cars on a travelling modular layout and these cars run well given the imperfect track conditions they're subjected to on a monthly basis. They also hold up well travelling in boxes to and from shows.
The only thing I don't like about these cars is the difficulty in weathering the car after assembly. If you're going to weather the ends, I recommend you paint the heavier parts of the weathering on, assemble the car and then finish with your favorite washes and powders. I made that mistake on my first two and now I can't apply road grime to the ends without reaching through the end cage with a tiny brush.
Overall, it's a nice car at a good price. Compared to a 40 ready to roll car, this car is lacking some of the finer details and the paint may not perfect, but is sufficiently well made to blend into a line of the nicer cars on a layout. If you're a modeler wanting to build a nice looking fleet on a budget, I can't recommend the Accurail PS4750 hoppers enough.