A sanded Fast will probably give more overall hook than a polished Furious, with a defined motion off the breakpoint. It's less elastic than the solid coverstock and therefore doesn't naturally want to roll as much in oil, but it's still got very open pores and lots of grooves in the cover to create friction in oil, and fresh, grippy surface for good response to dry boards. The polish on the solid cover will give it less friction in oil, and also less violent response to the dry. Whenever I've polished a solid, it's been good for keeping the ball smooth, but letting me move right. Whenever I sand a pearl, it's useful for creating some skid in the fronts, but still reading the lanes well and being very strong downlane, which is good for when the shot breaks down and I need to move left to chase head oil, but polished stuff is lazy off the spot downlane.