I've read some posts that the engineers personally took time to post here. It's a bad idea to put poly anywhere other than the knuckles on the rear suspension. Rubber is the way to go, and that's what I'm going to put on my rear end rebuild when I do it. I've got the poly knuckle bushings, but I prefer to keep within the engineering degree of safety. I tend to listen to the engineers when they have something to say. And in this case, he was very forceful about the use of poly...Don't do it in the rear suspension.
It's even been found that poly up front just doesn't work either. Especially the front strut rod bushings. As soon as they undergo a strain, they pop off.
Just wanted to pop in and let you know that it's not just arm chair racers who think it's not a good idea. The suspension engineer didn't think it was a good idea.