G'DAy again Sunspirit,
The Air-X is condemned by many for its high noise levels. In our experience, they ain't so bad as all that. We did take the trouble to carefully sand the blades down to a 600 grit finish, and that seems to reduce the low to moderate wind
noise (a sort of whooshy whistle??) a bit. We also carefully set the blades so that there is an identical distance between the blade tips. Seems that the sockets in the hub allow a bit of slop, and it is easy to get some slight discrepancies between the blades. Getting it right reduces vibration markedly, which reduces the transmitted noise into the hull
. Don't know why the vendor doesn't mention this in the instruction manual!
The real bad rep for these turbines is a holdover from the previous model 403. These had no electronic brake to avoid overspeed, but used flexing of the blades to limit speed in strong winds. The noise generated by this action was an unearthly howl, and was pretty unbearable!
I have several of the Breeze models on nearby boats and they do seem a bit quieter than the Air-X... but apparently at the cost of lower output. One wonders: half as loud, half as much peak power???
The advantages of the marine models are all in corrosion
protection -- powdercoating and maybe some additional seals
and anodizing. Aluminium corrosion
in a marine atmosphere is pretty hard to avoid, so I reckon that unless you are willing to disassemble a new unit and do a really good job of painting it (not easy nor particularly cheap
to do), the additional cost of the marine version is a bargain.
And finally, in a cruising environment
, carrying a spare set of blades is a good plan. We've had them lost
to birds and to errant halyards, and were glad that we had spares.
So, get out from under the pines and go sailing, mate!