I'm having some pitch taken out of my props, and the prop shop recommended application of PropSpeed. What little I can find on the 'net is not terribly helpful. They claim a 10% reduction in fuel consumption, and claim it will last "5-6 years". I did find a comparison to PropGold, but basically all it said was that the latter was preferred due to ease of application. Is this worth doing? Which product is better, or are there others I should consider?