They certainly take time and effort to get them under control. It is a learning curve that can be steep. On my J I was never able to get the vane to run tbe boat downwind for longer than 3 or 4 hours without some real steering issue. Using it on watch was far from relaxing downwind. The boat just had too much acceleration. It was a great backup, but never made it to primary steerer. With all the crap-on-de-back of so many cruising boats, tbere's no place to mount windvanes in clear air on alot of them. On my new boat I,m going with a redundant below deck AP. Overall cost will be actually less. No jungle gym on tbe back. There,s enough redundant power generation that I'm OK with that risk. The big risk is a lightening strike that takes out all.