One of the boats opposite me has one at the moment and its bloody noisy from 100yds away, what its like on the boat god only knows. When I looked into getting one for the (t)rusty old ketch one of the things i did was wander around marinas listing to them in a strong wind !

personally i bought a rutland 913 and have been very very pleased with it (so far) its been on the mizzen for 2 years and is the ONLY thing charging the batterys as the solar panels I have are useless (no bloody sun).