Harmonic balancer

There are many different factory part numbers. Some differences were due to the different timing mark locations, some due to forged or cast crank, and as stated stick or automatic trans. Also there were several variations with trucks, farm equipment, and industrial applicaton (multiple shives in a one piece cast damper), instead of bolted on stamped shives.
Several years ago someone did a test with slant six vibration dampers. The person took a forged crank, and put it on a crank balancer, and tried a few different balancers, and could find no difference. Even the total weight of the balancer was basically the same.
My personal thoughts (and I really don't have anything to base this on) are that the difference is the durometer rating of the rubber. That consideration is out the window after all these years on a stock used damper. I personally have used cast crank dampers on forged crank engines, and vice/versa.
This post pertains to the slant six only
EDIT: All the aftermarket replacement dampers I have seen applications for don't list as being different.
PS: Factory slant six dampers (car) for a forged crank have three wide "spokes". The cast crank dampers have six narrow "spokes."