We have a 3VCS, and manual states as mandatory procedures,
Servo:6v type Digital servo only. Presumably if you use analogue and blow it up, you're on your own.
3VCS comes with R203HF HRS receiver, although you can use other receivers by changing mode. Normal version comes with R113iP Non HRS receiver. HRS system seems to suppress interference better as well.
Hope this helps.
Phil