Who was the Dusters/Demons competition?

A Mopar A-body, like some AMCs were the (kinda) sleeper cars of the musclecar era. Back then not alot of people thought about horsepower-to-weight. Between marketing, relative low cost & availibility if someone heard of a big-block anything being availible at the dealer & could get a good price, they grabbed it.
I've seen quite a few smaller cars, not just Mopar A-bodies, easily spank big-blocks.
As to Mopar's A-body "competition"----L79 Novas, 351C Mustangs, Rallye 350s, 350 Tempests were kind of all in the same "class......