In 11 years and many many flying hours, I have never been in a situation where the autopilot is unable to maintain an acceptable flight path. If you have then I put it to you that you were somewhere you should not have been thus opening further questions.
You've perhaps never flown a "classic" airplane: on the 747-200 which I had the absolute honour and pleasure of flying for almost three years, disconnecting the automatics was often absolutely the only way to get out of sticky situations (like the autopilot turning the wrong way -towards the mountains of course- on localizer intercept).
On the equally lovely 747-400 I have been on for the last two years, I have already had to disconnect the A/P at least once as it was clearly doing something patently silly. Come to think of it, even on the ultra-modern A321 I flew for seven years, a couple times it went "wonky" leaving no alternative but manual flight (one classic example was the dual FMGC timeout as I recall).
The bottom line is, automatics are wonderful and quite reliable (especially on newer airplanes), but sooner or later they
will fail/misbehave. As long as the guys/girls on the "sharp end" are the type that use automation as a mere tool, are well aware of the attitude and thrust required for each phase of flight and are comfortable flying manually, it will be a non-event.
Automatics are your slave, NOT the other way around. By all means use them, but
depend on them at your own peril.
