Interesting to me is how much of the sailing fraternity will not put to sea without a GPS, state of the art chart plotter, AIS, HD radar, Iridium phone, the list goes on.
And yet there appears to be a preference to antiquated wind vane steering systems that (generally speaking) require control lines to circumnavigate the boat and end up cluttering the space that you spend most of your time in.
I don't know, in this part of the world, I'm certainly not seeing much of a "preference" for vanes, they're still pretty rare, and becoming more so, in my observation... Especially, among American cruisers...
I have long since converted to an autopilot that not only holds a better course either on the wind or off, doesn't take you off course when you're running off the wind (predominant cruising condition) and the wind shifts, uses almost no electricity (a modest solar array easily replaces anything the autopilot uses).
In the bad old days before fancy electronics, I sailed with an Aries windvane which in it's day was considered one of the best. Downwind sailing was a nightmare with crash gybes the order of the day. The "average" course it steered may have been brilliant in the days of bows and arrows but today?
Only vanes I've ever used are my Sailomat, and a couple of Monitors.... If their perfomance was anything like what you describe, I wouldn't think very highly of windvanes, either... (grin)
Funny that in an article in the current CRUISING WORLD entitled "Simply Indespensible", the crew of OSPREY list the essential gear that has worked best over their past 4 years of full-time cruising on their 45-footer... One of the 11 items selected, was their Aires vane... As always, different strokes for different folks - and they're certainly not for every type of boat, of course...
Further evidence that I'm a dinosaur among today's sailors, no doubt - but I still rate the purchase of my first Sailomat 15 years ago to be right up there with the best money I've ever spent...