If I let the autopilot turn me to a new heading, it will hunt for a
while.

Well, that's the least of it. The real issue is when you change
course, or just hit direct-to and nav. With GPSS, it gets on course
and stays on course, smooth as you please. Without, you need to get it
on course manually, set the heading bug correctly, then when all is
good select nav track. And even then, you have a choice of hunting in
enroute mode, or annoying wing waggle in approach mode.

I suspect you have fewer issues with this because you fly a much more
stable, solid airplane. The experience I have with these gadgets is in
Mooneys and Bonanzas.

I suspect the same issue applies to altitude hold. When I'm talking
about smooth air, I don't so much mean lack of turbulence as lack of
lift/sink. Your airplane doesn't have nearly the tendency to pick up
speed when the nose is pointed down that a Mooney or Bonanza does, but
the flip side of this is that lift and sink don't affect your airspeed
(and thus your pitch trim) near as much. Thus you don't get beeped at
to retrim every time the vertical speed of the air mass changes by 200
fpm - but in a Mooney without autotrim, you will.

Michael