IMHO...the plastic with metal and plastic detail is as nice as anything ive every seen. The 2 best in my opinion being the 8000 gallon tank car, and the USRA 2 bay hopper car. The AC-2 ACF covered hopper car is really nice too.
What is an SP G-50-9 anyway? The wood beet gonds with the high sides? The gonds have been made in SP, but not with the high sides. Some ppl have fabricated their own high sides for them