I just asked this question to a guy at my field, although I haven't seen how tight they fit in my Dolphin. He said to bend the metal ends how you want them. He said the wooden rods wont deflect like the metal ones will - if you use metal with the tubes, you may need to install a support somewhere near the center. You will notice that you can hold the servo in place and still move the rudder or elevator because the metal will flex. Wood supposedly doesn't do that, at least as much.