no wood dowel pushrods, higher torque servos, I had a TT 61 mounted as close to the firewall as possible and it balanced in the middle of the recommended range with the battery behind the tank, I was moving the cg back and had the pack as far back as the rear of the wing when I lost it on a deadstick. Too low, Too far away. I replaced it with a funtana and the jury is still out on whether that was a good idea, the snow has come after only a handfull of flights