If Gulfstream married Rolls-Royce and they had a kid, we imagine junior would be something like the 2013 Bentley Continental Flying Spur Speed. Melding a business jet-like interior with British motorcar charm, this luxury sedan accelerates like a G6 on take-off and cruises effortlessly at autobahn-level speeds. All the while, its fortunate passengers enjoy a roomy, serene and pampering cabin.

Essentially a longer, higher-performance four-door version of the previous-generation Continental GT coupe, the 2013 Bentley Continental Flying Spur Speed shares its sleeker sibling's turbocharged 12-cylinder powerhouse that makes this big bruiser's eye-opening performance possible. Fortunately, we doubt that most potential buyers of a Flying Spur Speed will consider its 14 mpg combined fuel economy rating to be a deal breaker.

Impressive as the Flying Spur Speed is, it is not without some formidable rivals. The 2013 Jaguar XJL, 2013 Mercedes-Benz S65 AMG and 2013 Porsche Panamera may not have quite the presence of the big Bentley, but they do offer a variety of engine choices and also provide roomy rear quarters and more up-to-date electronics. The Aston Martin Rapide offers sexy styling that's more sports car than sedan, though rear passengers pay the price with notably tighter accommodations. Lastly, those who can spend beyond the Spur's substantial price tag might also consider the more stately Rolls-Royce Ghost. As expected, there's not a bad one in the bunch, so we suggest driving the lot of them to help you with your decision. We could think of worse ways to spend a weekend.

The 2013 Bentley Continental Flying Spur Speed is a high-performance ultra-luxury sedan that is offered in one very well-appointed trim level.

Standard features include 20-inch wheels, a sunroof, keyless ignition/entry, an adjustable air suspension, bi-xenon headlights, front and rear parking sensors, four-zone automatic climate control, leather upholstery (incorporating many of the upgrades from the regular Flying Spur's Mulliner Driving Specification package), heated front and rear seats, 16-way power front seats with lumbar massage and rear-seat lumbar massage. Also standard is a 12-speaker sound system with six-CD changer, satellite radio, iPod integration, a navigation system and Bluetooth connectivity.

Options include carbon-ceramic disc brakes, power-adjustable rear seats with a full rear center console, flip-down wooden tray tables for rear passengers, a full-length three-passenger backseat, a heated steering wheel, ventilated seats, a rearview camera, a rear-seat entertainment system with twin display screens, a power-opening and -closing trunk, adaptive cruise control, a refrigerated bottle cooler and a 15-speaker Naim sound system.

The level of further customization is dizzying, as, in addition to the options mentioned above, one may specify their own paint and interior colors, as well as choose from various headrest embroidery, seat piping, accent stitching and steering wheel styles.

The 2013 Bentley Continental Flying Spur Speed is powered by a turbocharged 6.0-liter W12 that produces 600 horsepower and 553 pound-feet of torque. Power is channeled to all four wheels through a six-speed automatic transmission. Fuel economy is expectedly low, at an EPA-estimated 14 mpg combined (11 city/19 highway).

Standard safety features on the 2013 Flying Spur Speed include side and side curtain airbags in both front and rear. A passenger-sensing system in the rear seats automatically raises the rear headrests to ensure the best possible protection against whiplash injuries. Antilock disc brakes, traction control and stability control and front/rear parking sensors are also standard equipment. A rearview camera is optional.

The 2013 Bentley Continental Flying Spur Speed, with its nearly silent cabin, adjustable suspension and turbine-like W12 is capable of delivering the sensation of low-level flight rather than merely that of cruising down a long stretch of highway. Improbably, it also tackles back-road curves like a much smaller car. But compared to other large luxury sedans, the Bentley's bulk is undeniable, and it's just not as energetic to drive as cars like the Jaguar XJ or Porsche Panamera. If you're looking for transport that's more stately than thrilling, though, the Flying Spur Speed should certainly deliver.

Of all the luxury cars on the market, few can challenge the Bentley Continental Flying Spur Speed's exquisite interior. Only the finest leathers and wood veneers are selected, while time-honored craftsmanship shows in every detail. Push-pull vent controls, a Breitling timepiece and real metal switchgear give the cabin an old-world charm.

High-tech convenience contrasts with old-world charm, however, keeping the Continental GT Flying Spur Speed competitive with its contemporaries. The infotainment touchscreen interface is clear and its operation intuitive, and the instrument panel features a sharp digital display flanked by legible analog gauges. That said, some of the buttons and switches aren't as clear or easy to use as those of some competitors.