For a street application the ladder bars are a better choice & can be use with the leaf springs if floaters are used or coilovers & a panhard bar for a lighter system , I have built 2 street cars with the ladderbar / leaf system & have had incredable traction my Chall would hook on a 5" wide bias ply tire when I first set it up & my Duster would pull the front wheels 3' on slicks at the track with 1.50 60' times & even lift them on the street with a sticky street tire, I also ran this car as a street strip car for 10 years. the ladders can be installed with the addition of an extra crossmember 32" froward of the axle center & floaters on the housing with leafs or a second crossmember for the coilovers if the leafs are eliminated
The 4 link is more pure straight line race , & does not handle the stresses of cornering as well but it is more adjustable [not nessisarily a good thing with approx 200 settings] & is light. The 4 link basically requires the rear sub frame to be replaced to allow for the mounts for the 4 link & to make the frame stronger for the stress where the power is transfered to the chassis.
One of the ladderbar cars I had a part of building ran 2.6 seconds in 100' & timed at 54 MPH
& it had the ladderbars / floaters & a mini tub with about a 10" tire & is street driven