Of all structural points, the hull-to-deck joint takes the most abuse as hull and deck constantly alternate between tension and compression. It's a common source of leaks. Cobalt's solution uses a flush-fit joint in which the deck flange mates into a rabbet-a perfect-fit recess-on the hull flange. This rabbeted joint is self-supporting and water resistant, better than the typical shoebox fit. Plus, the joint is glued, bolted, and fiberglassed. Few boats possess as robust a hull-to-deck joint.
Fitted with twin 473-bhp Cummins MerCruiser QSB diesels and joystick-controlled Zeus drives, the 46 has the speed and efficiency to go with its looks. In joystick mode, the Zeus drives rotate in independent directions, while the onboard computer independently shifts each between forward and reverse and applies higher or lower rpm, also independently, to make the boat follow the simple movement of your hand on the joystick. Need to slide diagonally backward while countering a headwind to slip the boat in a cross current? Move the stick. The boat mimics the movement.
Zeus drives are more efficient than traditional inboards. Their aft-facing propellers are mounted in shallow tunnels. At 30 mph, my tester delivered nearly 1 mpg. Zeus drives also provide agile handling. It's worth a test ride to experience the sensation of zipping around in a boat this big. Part-time underwater exhaust (through-hull at lower speeds) and less vibration make Zeus-powered boats quieter than inboards, too. I recorded a hushed 82 decibels at 30 mph. Top speed is 37 mph.
This demonstrates excellent performance compared to straight shafts. But how does it compare to boats powered by Volvo Penta's IPS? IPS drives mount on the deadrise, the props face forward, and exhaust is underwater at all rpm. Formula's 45 Yacht ($931,200 with twin 435-hp IPS 600s) tops out at 37.3 mph, burning 31 gph at 30 mph while emitting 78 dB-A. Tiara's 4300 Sovran ($640,600 also with twin 435-bhp IPS 600s) hits 37.8 mph and burns 30 gph at 30 mph, emitting 82 dB-A. The Formula weighs 2,000 pounds less than the 46, the Tiara 3,000 pounds less. Both achieved marginally higher top speeds using less horsepower and burning less fuel at both full throttle and the 30-mph cruise benchmark. However, the differences in weight, as well as the boats' hard-sided coupe helm enclosures, are likely just as responsible for their better efficiency.
Picking a boat such as this is about amenities as much as performance. So head belowdecks on the 46. Hit a switch. The microwave rises out of the galley counter. Run your hands across the real leather, real granite, and real glass tile. The sensation is superior to materials preceded by the word "faux." At the fuel dock, enjoy the convenience of port and starboard tank fills. Fold out the solid teak cockpit table, cleverly hinged and hidden within the aft lounge backrest. In short, the more you explore this boat, the more it pleases. That, if anything, truly sets it apart.
EXTRA POINT: Spreading the stringers in the bow increases headroom. The sole is bonded to the stringers and athwartship frames are added, so hull stiffness isn't sacrificed.