Without the option of expo for one plane I built it would be far to twitchy in pitch to fly and where it was elevons there was no way to limit the throws mechanically with out reducing the roll rate which isn't all that great to start with.

I usually put expo in my planes on high rates and sometimes on low rates depending on the plane But none of my planes have expo in the rudder
it seems that I start adding rudder in and need just a bit more and then all of a sudden I get a handful of input than I am fighting to keep it straight. I generally do better when the rudder responds identical to my radio all the way through the curve.