I cannot find the post here now but there was one here from the Hitec guy that mentioned a new receiver with the 9x that had a 9ms update rate. My guess is that would work best with digital servos. Also that the 9X will be backward with the present Hitec Optima Rx. so you could use those with your present or future analog servos. That is what Iintend to do as Ihave 12 optima RXs and tons of analog servos. I would keep the new fast Rx for a future hot plane or sell it on Ebay or here.

Google around or search here and you will find more posts about A9X or Hitec will probably answer your question here eventuall.

Jim D