Jaguar XF vs. Acura RLX

In the luxury-car class, teaming refinement, performance, style, com­fort, and a plush cabin is merely the price of admission. Customers who spend upward of $50,000 expect composure and opulence across the board, including a hushed interior, a supple ride, and seamless integration of advanced technology.

The updated Jaguar XF and redesigned Acura RLX are lavish and well-equipped sedans, but they take very different approaches with their designs, appealing to different buyers.

The XF's dynamic prowess, with its ability to combine handling agility with a supple, controlled ride, make it sporty and fun to drive. It also delivers quick, effortless acceleration and surrounds you with a unique interior ambience. But its cabin is snug and hard to access, and rear visibility is wanting.

The RLX, on the other hand, has a more spacious, nicely crafted interior and a smooth, fuel-efficient powertrain. But that's where the good news ends. The RLX's ride comfort falls short for a car in this class. It suffers from slow steering response, with little feedback, and ungainly handling that robs the car of a sporty driving experience. Both cars suffer from complicated control systems.

Overall, neither car scored as highly in our tests as their better peers, trailing models from Audi, BMW, Infiniti, Lexus, and Mercedes-Benz in our Ratings. There are also better values at a lower price. The redesigned Chevrolet Impala, for example, is a more well-rounded and pleasing package overall.

Neither of these cars is recommended. The XF scored high enough in our testing, but reliability of the new powertrain is unknown. Earlier versions of the XF were much worse than average.

By contrast, we expect the RLX to provide very good reliability. But in our testing, its 74 overall score just misses the cut for a luxury car to be recommended.

The XF is a stylish, sporty, and plush luxury car that's a delight to drive. Its responsive handling and lively steering help it prowl the streets with agility, beating, yes, BMW at its game.

A 2013 update brings two new engines, an eight-speed automatic transmission, and all-wheel drive. We tested it with the 340-hp, 3.0-liter supercharged  V6 most buyers will opt for. That engine provides quick and effortless acceleration while getting 21 mpg overall—not bad for an AWD car with that much power.

The cabin, however, gets mixed reviews. It's quiet and well-equipped, with a distinct ambience and some unique touches. After you press the start button, for example, a rotary gear selector rises from the center console and the retracting air vents motor open.

But the center touch screen, which handles many controls, is confusing, distracting, and slow. It takes a bit of dexterity to slip in or out of the low-slung sedan with grace. And seating is a bit tight, especially in the rear.

Moreover, though our XF cost more than higher-rated competitors such as the  Audi  A6, it lacks some common luxury features at this level, and getting some desirable features requires that you purchase expensive option packages. If you want power lumbar, for example, you'll need to ante up at least $1,300 for an interior upgrade package.

A nimble feline. The XF is a driver's car, first and foremost. Steering is quick and communicates true feedback. The car carves through curves with lithe enthusiasm. When pushed to its high handling limits at our track, the XF showed tenacious grip and stayed balanced and composed. It posted a decent speed in our avoidance maneuver. But a wide 42-foot turning circle is a handicap when maneuvering in tight situations.

Though the XF's ride is absorbent and controlled, it might be too firm for some at low speeds, lacking the creamy suppleness of competitors such as the Mercedes-Benz E-Class. Noise levels in the cabin are low, but the XF isn't as serene as, say, an  Audi A6.

The sumptuous cabin is trimmed with wood and soft leather. Components are nicely finished and fit together well.

Supple front-seat cushions provide good support but are not the best in class. The driving position is snug and low; several of our drivers wanted to sit higher for a better view. A powered tilt-and-telescopic steering wheel lets most drivers get well situated.

Gauges are legible, but controls are not well-designed. The in-dash touch screen handles most functions, but it has small buttons that can be hard to access quickly and a small font that can be hard to read. You'll also need to page through menus that can respond slowly to your inputs. Physical buttons and knobs are used for some climate functions, but the radio has no tuning knob.

The automatic dual-zone climate system works well. But the rotary shifter and the engine stop/start system can be finicky. If the latter is too annoying, you can shut it off.

It's easy to make calls using voice commands, but there's no such control for navigation or audio unless you buy the convenience package. Mobile devices can stream over Bluetooth and USB, but the car's screen may not display some audio info, depending on the source.

The trunk is nicely finished but fairly shallow.

Overall, Acura's flagship sedan doesn't have what it takes to compete with models in this premium price range. This $55,000 model even falls short when compared with a $40,000 Toyota Avalon. It lacks the ride comfort, handling agility, and some features you'd expect to find in this lofty bracket.

Passengers are often jostled by a nervous ride, undermining the car's luxury intentions. Handling is ponderous. The muddled controls are too confusing for what should be a low- stress driving atmosphere. We were dismayed to find that some features that we'd expect on a $55,000 car, such as a heated steering wheel, are not even available.

The RLX's virtues include its richly finished interior, comfortable seats, and roomy rear. Another strong point is the smooth, refined 3.5-liter  V6 engine, which provides ample power and a good 23 mpg overall on the required premium gas. That said, you can keep $15,000 in your wallet and find those same qualities in large upscale cars such as the excellent Chevrolet Impala. Even the more plebeian Honda Accord V6, at $25,000 less, could be a more attractive option.

Most models are equipped with a smooth, six-speed automatic transmission and front- wheel drive. The powerful, pricier hybrid comes with a seven-speed automated manual transmission and all-wheel drive.

The RLX earned a 74 in our tests, which is too low to be recommended. Reliability, however, is expected to be very good.

Luxury letdown. One highly touted feature we found to be frivolous is the RLX's four-wheel steering system, dubbed P-AWS. The rear wheels turn slightly along with the front wheels at higher speeds, and inversely at low speeds. It's intended to enhance handling and maneuverability, but we noticed no benefit, and it doesn't seem to help the turning circle, which is 40 feet.

The RLX is hampered by lethargic steering that dulls handling and is devoid of feedback. At its handling limits, the RLX felt sloppy and tended to run wide in corners, but it proved ultimately secure.

Despite using acoustic glass and active noise control, sound levels aren't subdued, and there's notable suspension noise.

The interior is nicely assembled. Surfaces are padded or covered with wood, and the seats are well-tailored in perforated leather. The automatic climate control has three zones, and the front seats are heated.

Drivers will find plenty of room behind the power tilt-and-telescopic steering wheel, and the rear seat is one of the largest in the class. The  "jewel eye" headlights, another highly touted feature, are extremely bright but only illuminate an average distance ahead.

The RLX has two prominent screens: a large one on the center dash and a small touch screen below it. At first glance, the center controller and touch screen don't look complex, but they're actually confusing. Audio controls are messy, have small buttons, and have no dedicated tuning knob. Navigating through an overload of screens and menus is too much of a distraction for the driver. Using voice controls is easier but still cumbersome.

Mobile devices connect through USB or Bluetooth, and compatibility with some Internet radio apps is built in. Satellite radio and concierge services come with a subscription.

The trunk is large and nicely finished, and has a center pass-through. But the rear seats don't fold down to increase cargo space.