In Short, Yes!
If you race, you need a folding or a feathering prop. Although the 2 blade is less drag than the three bladed sea anchor that came on my boat, it is noticible. The option of lining the prop up with the strut helps a lot, but if you are serious, not enough. On my previous boat ( a cal 27 with a 2 blade fixed prop), I discovered that the boat was faster if I allowed the prop to spin. It was a bit unnerving to hear that noise, but it was faster.I bought a 2 blade Martec for my current boat (a C-30T) which I both cruise and race on Lake Michigan. The only down side that I have noticed is an inability to power into a 6' chop with 20+ MPH headwinds ... my speed at full throttle was 1.5 mph! As I usually sail, this one limitation is minor. As for stopping the boat using reverse, it is necessary to "goose" the throttle to get the blades to open. Not a problem, but if you are gentle, they might not open until you are several feet into your pier!I've looked at other brands of folding props, and don't have much to choose between them. The Gori is geared and may be more reliable in opening ... but it is more expensive than the Martec. The CDI is less expensive, but has more drag. You pay your money and take your choice.Good luck.Steve