"Grace, space and pace." Such is the slogan that Jaguar once used in its advertisements, and it holds true for the modern-day XJ. Though the XJ adheres to British tradition, one could see it as a non-conformist in today's luxury market: It is neither as conservative as the Germans nor as flamboyant as the Italians. The XJ lacks the sporting intentions of its Continental rivals but it has plenty of straight-line performance thanks to a series of supercharged V6 and V8 engines and a choice of rear- or all-wheel drive. Instead, the 2016 Jaguar XJ derives its character from its elegant sense of design. Its purpose is not to quicken your pulse, but to relax it.

The 2016 Jaguar XJ won't be confused for anything else on the road thanks to its sleek design.

Jaguar offers the XJ in both short- and long-wheelbase models, the latter offering optional two-place reclining seats with fold-down trays and heated and cooled seats with a massage function. Though the XJ lacks some of the high-tech driver aids found in its rivals, it emphasizes comfort and luxury, with features such as a self-leveling suspension and double-paned glass as standard.

Lovely as it looks, the XJ lacks the vault-like feel and the high-end features found in German rivals such as the 2016 Audi A8, 2016 BMW 7 Series and 2016 Mercedes-Benz S-Class. Also absent are fuel-efficient powertrain options such as a hybrid drivetrain or a diesel engine, and together these missing pieces have resulted in an Edmunds.com "B" rating. But for those who favor comfort and opulence over nifty gadgets to show off to the neighbors, the 2016 Jaguar XJ offers timeless appeal: grace, space and pace indeed.

The 2016 Jaguar XJ is a five-passenger (four in some configurations) full-size luxury sedan available in regular (XJ) and long-wheelbase (XJL) variants. The XJ comes in R-Sport, Supercharged and XJR models, while the XJL offers Portfolio, Supercharged and XJR trims.

The R-Sport base model comes standard with a supercharged V6, 19-inch wheels, an adaptive and self-leveling suspension, driver-adjustable steering and throttle settings, shift paddles, front and rear parking sensors, a rearview camera, automatic wipers, automatic adaptive bi-xenon headlights with automatic high beams, auto-dimming mirrors, a panoramic sunroof, blind spot monitoring with cross-traffic alert, keyless ignition and entry, and leather upholstery.

Standard convenience equipment includes soft-close doors, a power trunk lid, dual-zone automatic climate control, heated and cooled eight-way power front seats (with four-way power lumbar), driver seat memory settings, a power tilt-and-telescoping heated steering wheel and heated and cooled rear seats.

An 8-inch touchscreen system anchors the multimedia features, augmented with a standard navigation system, Bluetooth phone and audio connectivity, voice controls, the InControl app suite, a WiFi hot spot and a 14-speaker Meridian audio system with a CD player, satellite radio, HD radio, digital music storage and a USB connection.

Options packages for the R-Sport include the Comfort package with 14-way power front seats with massage functions, front passenger seat memory settings and four-zone climate control. The Parking Assist package includes a surround-view camera and (for rear-drive models only) an automatic parking system. Stand-alone options include adaptive cruise control, an upgraded stereo, additional cabin illumination, a heated windshield and a wood-and-leather steering wheel.

The 2016 Jaguar XJ's interior isn't as tech-forward as its rivals, but the cabin is certainly inviting.

The Portfolio model is exclusive to the long-wheelbase model, and adds unique exterior trim, upgraded leather upholstery, four-zone automatic climate control, 14-way power-adjustable front seats with massage functions, rear LED reading lights, an electric rear window sunscreen and manual rear-side-window sunscreens. The options list is similar to the R-Sport, with the addition of a Premium Rear Seat package that includes two individual reclining rear seats with memory function and footrests, winged headrests (for the front and rear seats), electric rear-side-window sun screens, fold-down tray tables and a rear seat entertainment system.

The Supercharged model is available in both regular (XJ) and long-wheelbase (XJL) versions. In addition to the Portfolio's standard equipment, it includes unique exterior trim, a supercharged V8, an active rear differential, tauter suspension tuning, 20-inch wheels with performance tires and larger brakes. All of the XJL Portfolio options are available.

Top of the line is the XJR, available in regular and long-wheelbase versions. It comes with the most potent Jaguar V8 engine of the range, exclusive 20-inch wheels, premium paint colors (which are an extra-cost option on lesser XJs), XJR-specific suspension tuning, an active exhaust system, sport seats (which lack a massage function), a heated steering wheel and unique interior trim. However, the premium rear seating package is not available with the XJR, nor is the upgraded Meridian stereo.

The 2016 Jaguar XJ R-Sport and XJL Portfolio models feature a supercharged 3.0-liter V6 engine generating 340 horsepower and 332 pound-feet of torque. An eight-speed automatic transmission and rear-wheel drive are standard; all-wheel drive is optional.

EPA-estimated fuel economy is 21 mpg combined (18 city/27 highway) for the rear-drive model. The AWD model is rated at 20 mpg combined (17/26), up 1 mpg from last year's ratings. On Edmunds' 120-mile mixed-driving evaluation route, we were impressed with the 24 mpg delivered by an XJL Portfolio AWD.

Upgrading to the XJ Supercharged model gets you a supercharged 5.0-liter V8 with 470 hp and 424 lb-ft of torque, while the XJR extracts 550 hp and 502 lb-ft of torque from a higher-performance version of this engine. Both models return an EPA-estimated 18 mpg combined (15/23). We coaxed 22 mpg from a long-wheelbase XJR on our evaluation route.

In Edmunds testing, a Jaguar XJR (LWB) accelerated from zero to 60 mph in just 4.1 seconds. An XJL Portfolio AWD required 6.1 seconds in the same test, which puts it a little short of best-in-class acceleration.

The XJR scoots from zero to 60 mph in just 4.1 seconds, an excellent time for a flagship luxury sedan.

Every 2016 Jaguar XJ comes standard with antilock brakes, stability and traction control, front side airbags, side curtain airbags, active head restraints, a rearview camera and a blind-spot warning system. A forward collision alert system and advanced brake assist (primes the brakes if an accident is imminent) are included with the optional adaptive cruise control.

In Edmunds brake testing, an XJL Portfolio with the standard 19-inch wheels and all-season tires stopped from 60 mph in 124 feet, a bit longer than average for this class of car. An XJL Supercharged with summer tires and its larger standard brakes, however, stopped from 60 mph in 106 feet. The similarly equipped XJR did it in 105 feet. Both distances are shorter than average for the segment.

Conspicuous in their absence are brakes that are automatically applied (if a collision is imminent), lane-keeping warning/assist, a head-up display and night-vision capabilities. Many of these high-tech safety enhancements are either standard or available on other manufacturers' flagship sedans.

The Jaguar image is one of effortless speed, and the 2016 XJ's gracious road manners don't disappoint. Quiet as they are, however, both the XJL Portfolio and XJR we drove still had trouble damping out harsh road impacts. Aluminum construction makes the XJ lighter than it looks, and the Jag has an agility that some rivals can't match. Driver-selectable settings for the engine and transmission provide discernible differences and enable softer or more aggressive responses from the driveline.

The supercharged V6 pulls strongly, offers decent fuel economy and will hit the sweet spot for most buyers. It sounds great, too. But if it's outright power you crave, either of the beefy supercharged V8 engines will deliver. The Jaguar XJR tops the lineup with the most power and a firmer suspension. While not punishing by any definition, the XJR is best suited to the driver who appreciates, and intends to exploit, its performance potential. The XJR isn't likely to be spotted at a track-day event, but this highest-performance model in the 2016 Jaguar XJ lineup is hugely satisfying when you crack the whip on the open road.

Settling into the elegant interior of the Jaguar XJ makes you realize just how austere and clinical other high-profile luxury sedans have become. This Jaguar is impressive thanks to high-quality leather surfaces set off with brilliant chrome and exquisite ambient lighting, but the parts selection and overall build integrity doesn't fulfill the promise of a flagship quality that competitors' similar sedans offer. Liberal use of plastic and many parts clearly shared with other Jaguar cars takes away some of the exclusivity of the top-tier XJ.

Old World luxury meets contemporary aesthetics with a digital instrument panel replicating mechanical dial indicators in a variety of user-configurable layouts and bathed in soothing ice blue and alternatively racy-red hues. The XJ's touchscreen interface commands most of the sound, navigation and phone controls. We've complained about the interface in the past; Jaguar has updated it for 2016, but we still find competitors' systems (typically manipulated via one large control dial and adjacent menu buttons) easier and quicker to use.

Although its vast exterior profile suggests otherwise, the XJ's sloping roof line sacrifices both front- and rear-seat headroom for style. In the short-wheelbase models, there's also not as much legroom in the rear as you'd expect. If you need a roomy backseat, consider the long-wheelbase L models, but no XJ will feel as limolike as some of its competitors do. Similarly, the XJ's 15.2-cubic-foot trunk is average in size for the segment and has a few awkward protrusions as well as a shallow profile that limits your loading options.

The 2016 Jaguar XJ's sloping roof line cuts into rear passenger headroom.