A Autohelm/Raymarie ST-50 transduser was istalled to our mast head on 1996 when the boat was launched by the previous owners. Last September, I finally had to take it down for its first service
- the bearings were out. I think that is pretty reliable.
There are mechanical bearings, however, the wind data is collected through Hall-sensors, so it is only the bearings than can wear out. Nothing else to be fixed. The cost was a little bit less than €100 (about $125) here including shipping
the transducer back and forth. $10 per year to keep it up and running. Not bad. Unless your problems are due to lighting
, I sure would vote for Raymarine on this one.