The flats, plow, Difco and hopper are from Walthers. The Difco and Greenville cars were from their "second" entry into N scale and came equipped with 100T roller bearing trucks with Accumate couplers. Their detail was quite good, on par with Atlas's Presureaid covered hoppers or the 23k gallon ACF tank. The GSC car is older, from the early 1990's. There were two distinctly different versions of this. The first run (1993-1995 I think) had awful trucks and poorly cast details. The stirrups and grabs were retooled around 2006-2008 and that car is much better. These are cast as a single part unlike the Athearn car which has a separate deck. The Athearn car looks better and its much easier to weather, but the Walthers car tracked better.
My guess is that the Airslide was a BLMA project.
