I had a 913 on my last boat. it was great cause it was VERY quiet as opposed to those screaming air marines. I could not live next to one of those suckers. When the wind
is up, it is noisy enough on a sail boat without having that banshee reinforcing the message.
HOWEVER the Rutland
was no where near as efficient as AM's. Most times it only put in 3 amps, maximum I ever saw was 9 amps at 30 kts of wind
(not boat speed)
On my new boat I spent the bucks on an extra solar
panel. In northern Oz, I think solar
will give me more bang for my buck, especially as we seem to be in a state of perpetual drought down under.