Study the attached picture - what you're seeing is a prop that was painted with propspeed, than sat in the water for 6-months and hauled again without running. Notice the blade where the guy with rubber glove has just brushed away the growth. I know of no other paint that will give that type of result. It must be professionally applied - there are some tricks to it that do not led itself to a 1-time DIY operation.
Despite the cost, I'm a buyer. -- M/V Weebles 1970 Willard 36 Sedan Hull #40 Ensenada, MX