I've been trying to get the boat propped just right for a while and have tried both Viper and Rebel BRP props with a variety of pitches. Today went out with a couple of Apollo props fitted with a slightly smaller diameter of 14 1/8 and 19" pitch which now has the engines hitting the required revs at WOT.
What I was extremely impressed with was the grip in tight high speed turns, considerably better than the BRP props, with the engines trimmed right up at 48knts you could pull into a tight turn with no loss of grip or cavitation. Amazing considering that these props were nearly half the price of the BRP ones.
Just a thought for anyone looking at nice shiny new props.