I'm all for anything that improves a cars handling but rose joints on road cars make me nervous... they just get too much of a pounding on normal everyday roads.

I'd just stick with urethane bushes, they are easy to replace and importantly you can feel/see them wearing out. With rose joints the first you know something is wrong is when they snap - and naturally that usually happens at a point when you really have them loaded up. That's not the best thing to have happen when you are on a race track but at least that's a controlled area - on public roads roads it's something you just don't want to think about.