on a rudder I wouldn't use a servo saver,I have them, and use them, but on aplications like my, air valve servo for retracts where the throw is a little too much for even a micro servo and the EPA(end point adjustment) doesn't take out the buzzing in the servo.
not in a make or break location like a rudder,elevator,etc....

if your getting too much throw in a control surface or alot of buzzing,which a little is some times impossable to stop,the pushrod needs some adjustment either at the servo or the control surface.

control surfaces should have a firmness to them esspecially when there on a quick plane like yours having a spring loaded connector is a invitation to flutter,or worse a screw loosening up durring flight.

and if you have it tightened up enough to prevent flex and flutter, then there is no reason for it to be there.

you might as well have the pushrod with a Z bend or a L bend with a quick connect at the rudder servo there is a solid and pretty much fool proof connection.