Of B&G Hydrapilot will make a much more agressive adjustment if you're close to a waypoint than if it's, say, 80 nm away.

The AP wind sailing algorithms of the autopilot seem to be the biggest difference, followed by the adjustments for sea state. Ours will fall off after a tack or jibe, then then fine-tune up like you were trimming to maintain speed. In stronger wind, it treats it differently than light winds. The sea state adjustments are aimed at not over correcting for wave trains in rough weather the same as in flat water. (I think ti does this calculation by the boat's periodic course headings and attempting to establish patterns for effectively correcting.) The algorithms are really the kind of thing that "Otto" would do if he weren't "Auto" the pilot. ;^)))

Autopilots have come a long way from the old Autohelm with a seastate knop and a roto-dial.