I messed up when I ordered my boat, I decided that since I was going to lift store my boat I didn't need to spend the extra money. But now I have found out that the composite drives are 10% more hydrodynamic and lighter. All of which adds up to free speed! Could have gotten maybe 1-2 mph out of the boat just by getting the composite drives instead. That is one of the downsides to the regular duoprop drives, they kind of hit a wall at around 60mph or so. Because they are so heavy duty under the water, they are just not as hydrodynamic as the bravo III's.