Cal Tracs rear suspension or multi-link suspension kit?

I'd sure appreciate it if somebody could explain to me why you would choose one or the other. I'm not very smart about suspensions. Right now the rear suspension on my car is composed strictly of mix-n-match parts (it's pretty lousy!).

I'm leaning toward a Cal Tracs because I really like the way they have a special version for use with leaf springs that have been relocated inward, which my car has.

I'd like my car to be primarily a road car, a corner-carver, but I need to make occasional forays to the drag strip in order to maintain my credibility (such as it is!) with the FABO crowd.

Thanks for edumacating me!