Introduced in 1970 and built in only a few hundred units through 1972, the Buick GSX is one of the rarest muscle cars from the golden. Conversely, the Plymouth Duster 340 is a rather common rig.

Compared to more well-known vehicles, like the Chevrolet Chevelle, the Dodge Challenger, and the Plymouth 'Cuda, Buick's GSX makes for some highly underrated muscle — even despite the bright ...