A friend of mine installed an Indigo on a C+C 30 with an A-4 and it definately improved the performance and handling. However, on the last haulout, after 2seasons in the water, there was'nt much left to the prop. The galvanic corossion had taken 3/4 inch off each blade end and riddled the rest with holes. He hadn't installed shaft zincs as suggested by Indigo to eliminate
propeller barnacle growth by allowing a small galvanic reaction to zap them away. After spending a winter in the water at a marina locally known for its stray electric current, and with his boats internally bonded grounding system between engine and thru-hulls, the electrical current apparently entered his thru-hulls and exitted thru the prop taking most of it away. To Indigo's credit, they offered him a new prop for 1/2 price and he thought highly enough of it's performance to buy another.
So, the new prop also has a pair of new shaft zincs to keep it company.