Talking to people doing circumnavigations with autopilots, the great majority (70%?) have had significant problems. Redundancy is your friend, either two autopilots or autopilot and vane.
Back in the water in Grenada - with new main and #2 and cockpit canvas (Santa came early). Will spend the winter and early spring in the Caribbean and then head to Bermuda and the northeast US. Still trying to decide if we will bring the boat to Canada, either in 2015 or 2016.