Hi all, I'm using savox high voltage servos and have read they are power hungry, do I need one of these in a nitro buggy?

Since nitro buggies use a battery pack instead of the BEC of an ESC, there should be no need.

Correct, those capacitors are for use with electric powered cars that the electronics run off of the speed control's BEC. If the BEC isn't strong enough, then when using the more power-hungry servos the BEC can be hit with more current draw than it can handle & the voltage to power the receiver can drop, which causes brown-outs. That's where the caps come in, they can draw & store a bit of current while everything runs, & if the BEC voltage drops too low, then the cap will discharge & help keep that voltage up briefly, hopefully long enough to avoid the brown-out. But since Nitro cars have a dedicated battery to run the receiver, the cap is not needed....

Awesome guys, cheers!!!