A number of high-powered deck and pontoon boats can run fast in a straight line. What sets the SXi apart is its cornering and open-water performance. Starting with its proven Power Deck hull, PlayCraft fabricated a new, all-composite bottom that is known as the FlexSpeed hull. At dockside, we noticed how the hull's triple-sponson design made for excellent stability. But at speed, it behaved more like a V-hulled performance boat, carving smooth arcs and slicing through chop with minimal pounding.