One of the nice things about the Sullivan push rods is that they are flexible and slide very cleanly through their tubes. I have used both Goldenrods and their carbon fiber rods. As long as you secure the tubes in several places along their route, they work just fine. If you don't secure them right or in enough places (like at each former) with epoxy (rough up the shell at the point where you would apply the epoxy), and at both ends, you can get them in some pretty ackward places.

CGr.