CH provides the caveat to avoid metal throttle rods in order to alert everyone that an issue with RF could occur in various situations. They also provide the direction that the user should do a complete range check to be assured there are no issues with RF. That range check should be done twice. Once with the engine running and once with the engine off. A difference in range of 10% or greater between the two checks would indicate that there may be a problem and should be looked into before flying the aircraft.

If there are no notable differences in range checks using a metal or carbon fiber pushrod, then you will be safe to fly providing you installed a break in the rod connections at both ends such as a plastic clevis or a ball link that is housed in plastic. I have been using both types of pushrods, C/F and metal, for years without issue, but the range check has always been an important part of the preflight.

Any of the better radios in use today should provide up to 150' or better in the range check with the engine running. If you are using a Futaba transmitter/receiver, ignore the manufacturer notes that a 50-75' range check will be adaquate. It's not and should be a lot greater.

Enjoy your plane,
Pat