My NC 33 Zarzuela has its original autohelm (intalled 40 years ago). Electric motor in locker below wheel, bicycle chain to ratchet behind the wheel, rods to rudder stock with wheel position indicator and a dedicated transmitting magnetic compass in the bow locker (needs special deviation table as close to anchor chain locker).
When close hauled i set full sensitivity and max rudder angle. In a strong wind, and even with manual steering, Zarzuela will fly up into the wind on account of her too small rudder.
Down wind I set 10 degrees rudder and low sensitivity but again, in a strong wind, the small rudder fails to keep charge and a crash jibe can ensue so would be in manual steering.
In F3 or less I find my autohelm brilliant and, particularly if sailing single handed, enables me to get on with the other tasks safely.