Yes you can fly stadard servos on a UCD..even rudder,,
I have been flying mine for about 6months now on stadard servos.. but I dont fly with any speed ,,3D stuff is slow and LOTS of THROW !!

)..I have a YS 120 on mine,,I flew one today with a brand new Saito 91,,It will hover it but it is at upper end of the throttle but will pull out . not great but it will,,But then this was only 4th flight on the engine..Just my two cents..

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