I agree, the triangulated 4 link is a compromise. GM used them before the fox body of course, including even in the Aussie Holden Toranas like I have. They have been road raced since they came out in the 70's and have been very good at it. But...the factory 4 link setup does as mentioned bind and is not an ideal setup if you are doing it for road racing.

I know a bunch of people who race competitively, and leaving the rear suspension stock is usually only done if the class dictates it.

Some guys as they did in the 70's just add a panhard bar, but that induces a bind when used with the triangulated upper arms. Going to soft upper bushing helps some but then you end up with more movement.

Some class guys that need to keep the stock location arms run basically sponge rubber bushings to make the stock upper arms useless, then add a 3rd center arm and a panhard or even better still, a watts link.

From scratch people who can run anything seem to be going with a similar 3 link setup with a watts link.

If you were going to run a different suspension setup like going going from Mopar leaf to anything from scratch, I think that would probably be a better route to think about.

That said, the triangulated 4 link is not terrible, and do know guys who are very competitive with them when they have no choice and are limited to it, but it still is not the best.

The length of the arms, and lots of other things play a big factor too, and you'd want to make sure they were designed for correct instant center, roll center, etc and not just what was best for packaging.