A grand touring coupe or convertible should engage the senses and inspire the imagination. It's the sonorous rumble of its exhaust, the sensuous curves of its styling and the cosseting confines of its interior that make you perpetually wonder, "Where shall I go next?" Being just a car is not enough; a proper GT should be an experience whether you're schlepping to work or trekking to Vancouver on a whim. The 2011 Audi S5 is without question one of these cars, capturing the essence of more expensive and exotic GTs in a more affordable, yet still incredibly sexy package.

Like many GTs, the 2011 Audi S5 is available as a coupe or a convertible, the latter of which is known as the Cabriolet. Though both are similarly equipped and come with all-wheel drive, each has a significantly different character due to unique engine and transmission choices. The coupe gets a more traditional configuration, with a melodic 354-horsepower V8 feeding its power through a six-speed manual or six-speed automatic transmission. The Cabriolet gets a more modern design, with a 333-hp supercharged V6 that matches the V8's acceleration potential but betters its gas mileage thanks in part to a high-tech seven-speed dual-clutch automated manual transmission.

Regardless of body style, you can expect the same high-quality cabin with top-notch materials, the latest electronics and sport seats that'll treat your backside superbly on that jaunt up to Canada. The Cabriolet might not have a retractable hardtop like several of its competitors, but its multilayered soft top quells outside road noise even as it minimizes any convertible's inevitable weight increase.

The styling part of the GT equation goes without saying, as the S5 is quite simply one of the best-looking cars on the road. Of course, there are other luxury coupes to consider. The 2011 BMW M3 is more of a driver's cars rather than a GT, and it's better suited for an aggressive assault on a back road. At the opposite end of the equation, the 2011 Mercedes-Benz E-Class is a little more sedate than its Audi rival. All this makes the 2011 Audi S5 a happy medium for those looking for a grand touring car that'll engage and inspire.

The 2011 Audi S5 is available in coupe and soft-top convertible (Cabriolet) body styles. Both feature Premium Plus and Prestige trim levels.

The Premium Plus comes standard with 19-inch cast-aluminum wheels, performance tires, automatic xenon headlights, LED running lights, foglights, automatic wipers, heated eight-way power front seats with adjustable lumbar and driver thigh support extension, leather upholstery, a tilt-and-telescoping steering wheel, tri-zone automatic climate control, a split-folding rear seat, an auto-dimming mirror, Bluetooth, the dash-mounted Multi Media Interface (MMI), a CD player, satellite radio and an iPod interface.

In addition to this, the coupe features a tilt-only sunroof while the Cabriolet features a fully powered soft top and a wind deflector. The Navigation package adds a rearview camera, rear parking sensors, center-console-mounted MMI controls, a navigation system, voice controls, real-time traffic and HD radio.

The S5 Prestige adds auto-dimming exterior mirrors, keyless ignition/entry, the Navigation package and a 14-speaker Bang & Olufsen sound system (optional on Premium Plus). The Prestige can be equipped with optional adaptive cruise control, a blind-spot warning system, a power rear sunshade (coupe) and the Audi Drive Select package, which includes a sport rear differential and driver-selectable settings for an adjustable suspension, throttle, transmission and steering.

Optional on both trims is a Titanium Sport package, which adds special dark-colored wheels and a black grille surround. The coupe can be equipped with a Sports Rear Differential package, which is basically the Audi Drive Select package without the suspension and steering adjustments. The convertible can be equipped with the Comfort package, which adds a neck-level heating system, ventilated front seats, adjustable front seat lumbar and upgraded leather upholstery.

The 2011 Audi S5 coupe and convertible feature completely different engines.

The Audi S5 coupe gets a 4.2-liter V8 that produces 354 hp and 325 pound-feet of torque. A six-speed manual transmission is standard and a six-speed automatic with manual control is optional. In performance testing, a manual-equipped S5 coupe went from zero to 60 mph in 4.9 seconds. EPA-estimated fuel economy is 14 mpg city/22 mpg highway and 17 mpg combined with the manual and 16/24/19 with the automatic.

The Audi S5 convertible is powered by a 3.0-liter supercharged V6 good for 333 hp and 325 lb-ft of torque. A seven-speed dual-clutch automated manual transmission is standard. In Edmunds performance testing, the S5 Cabriolet got from zero to 60 mph in 5.3 seconds. Estimated fuel economy is 17/26/20 mpg.

The 2011 Audi S5 comes standard with antilock disc brakes, stability and traction control, and front seat side airbags. The coupe has standard side curtain airbags and the convertible features pop-up roll bars. A blind-spot warning system is optional on the Prestige. In Edmunds brake testing, both S5 body styles came to a stop from 60 mph in 110 feet -- solid performance for a luxury performance car of this type.

The 2011 Audi S5 is a sharp-handling car, with tenacious AWD traction and little body roll to speak of. It's also rather heavy, however, and feels the part. In other words, it's a classic grand touring car that happens to handle extraordinarily well.

The standard 19-inch wheels and tires give the S5 a firm ride and notable road noise over some surfaces, but neither trait is objectionable by the sporty standards of this segment. The S5's standard speed-sensitive power steering system, on the other hand, feels artificially light at parking-lot speeds and too heavy on the highway. The optional variable-ratio steering system that comes with the Audi Drive Select package provides an even more contrived feel.

The coupe's 4.2-liter V8 is simply one of our favorite engines. Acceleration from this motor is authoritative, yet it never seems to be working hard, emitting an intoxicatingly mellow burble from idle to redline. The Cabriolet's supercharged 3.0-liter V6 is smooth and strong, and its automated dual-clutch manual works superbly. However, the V6 lacks character compared with the V8.

The S5's attractive cabin is one of its strong points, though the competition has largely caught up to Audi's formerly segment-leading interiors. Audi's Multi Media Interface (MMI) routes many functions through a control knob mounted on either the dashboard or the center console, depending on whether the optional navigation system is present. The dash-mounted version can be frustrating to operate, but the console-mounted one is the most user-friendly MMI yet, thanks to Audi's latest third-generation menu structure and a special joystick-like button atop the control knob.

The front sport seats are excellent for both enthusiastic driving and long-distance cruising. Of course the S5 features a low seating position and a high cowl and beltline, which is sportier but might make shorter drivers feel submerged. As with most coupes, the head- and legroom in the rear seat is limited, though people stuck back there will be treated to their own set of climate controls. The rear seatback folds down in both the coupe and convertible to accommodate larger cargo items, a welcome convenience in a high-buck performance car.