They are hardly effective for handling and removing unsprung weight. One reason I've always hated funnycombs is they only detract from a good handling suspension because of the unsprung weight disadvantage. I also don't like the look of them personally, never did. Rally II wheels are also lighter, and just as strong as the funnycombs.
Herb Adams and his bunch of suspension engineers put all that time into making an F body handle well, then someone decides it would be a good idea because of aesthetics to hang a cast poly wheel on all 4 corners of that finely tuned suspension, I never really understood that move..............
Some other GM divisions used cast poly wheels too, but thankfully it was just a fad, chevy comes to mind on the monte carlos.
They could have cast them from concrete, probably cheaper than poly, and only slightly heavier.......................
If you look at the wheels on my third signature picture of the 69 GP dirt car, that's what the wheels look like with the cast center removed. Theu're similar to a chevy rally wheel with triangular slots instead of oval slots. The centers are fairly thick and hold up to heavy lateral stress seen in oval track racing.