Quite common in some of the yards around here. I recently came across two remote control platforms on one train. Turns out one each from a different manufacturer. The CSX 9100 series are CANAC remote equipment and the 9400 series are CATRON. Notice the difference between the two bodies. The 9192 is 50000+ pounds heavier which explains the long rectangular block located centrally on the frame.
CATRON remote platform
CANAC Remote platform
Venerable workhouse, CSX 2637, GP38-2