Those wacky Germans have found a way to explore every automotive niche known to man--and invent a few of their own. The BMW and Mercedes-Benz product lineups have grown to include every manner of coupe, convertible, sedan, crossover, coupe-like crossover, hatchback sedan, and veloco-transport, plus numerous performance versions of each.

Audi has taken a more measured approach. Yes, the standard body styles are there, but Audi has only explored the oddball stuff once. It came in 2010 with the release of the A7. This mashup of a sedan and a hatchback, a Sportback as Audi calls it, was immediately lauded for its beautiful looks and it quickly garnered strong incremental sales for the brand's mid-size A6 lineup.

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For 2018, Audi is taking that idea to its compact A4/A5 range with the A5 Sportback and its more powerful sibling, the S5 Sportback. The idea is to add incremental sales to the compact segment while providing a sexy alternative to the coupe and a practical option versus the sedan.

2018 Audi S5 Sportback

2018 Audi S5 Sportback

2018 Audi S5 Sportback

2018 Audi S5 Sportback

2018 Audi S5 Sportback

2018 Audi S5 Sportback

More than a sedan with a backpack

"We did more than make the A5 Sportback an A4 sedan with a backpack," said Barry Hoch, director of Audi product planning North America.

The proverbial backpack of which Mr. Hoch speaks is the hatchback that the A5 Sportback, um, sports. Had Audi designers just started with the A4, and extended the roofline to create a hatchback they would have ended up with something akin to the BMW 3-Series GT—a taller hatchback lacking elegance. Instead, they wanted a baby A7, with the grace and beauty of that car.

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To accomplish that goal, Audi's design team, led by Frank Lamberty, started with the A4's wheelbase to get the appropriate length (it's 2.4 inches longer than the A5), then used the A5 as design inspiration from the A-pillars back. Effectively, that meant lowering the roofline 1.7 inches, stretching the coupe-like profile almost all the way to the rear spoiler, adding frameless side windows with the rear kickup from the A7, and using the coupe's more dramatic side sculpting.

2018 Audi S5 Sportback

2018 Audi S5 Sportback

2018 Audi S5 Sportback

2018 Audi S5 Sportback

2018 Audi S5 Sportback

2018 Audi S5 Sportback

The result is a car that fits between the coupe and sedan in terms of rear seat space, and exceeds even the sedan when it comes to overall practicality. Compared to the A5/S5 coupe, the Sportback has 0.4 inch more front head room, 0.9 inch more rear head room, and 2.4 more inches of rear leg room. Head room and leg room are both within 0.6 of the sedan's measurements, but the sedan has a 13 cubic-foot trunk, while the Sportback offers 21.8 cubic feet of rear cargo space in its hatch area and that can open up to 35 cubic feet with the rear seats folded down.

How does it work for people and their cargo? The rear seat has good space for a 6-footer to fit behind a 6-footer, but head room and especially leg room start to become tight as the mid-major college point guards start giving way to shooting guards or small forwards. Two adults will fit back there just fine, but the unsupportive middle seat will only work if all three are kids or 1990s waif models. The biggest issue, and it's not really a big one, is that the coupe-like roofline means taller folks will have to dip their heads and perhaps strain their necks when getting in or out.

The cargo story is even better. The hatchback body style makes for a generous cargo hold and the low liftover height makes it easy to access. The coupe-like roofline means it isn't as roomy as a wagon or crossover, but the car looks better. And the rear seats are easy to fold down from the side doors, opening up the full 35 cubic feet.

Sportier than the A4

In addition to its looks, the A5 Sportback is outfitted to be a bit sportier than the A4. It sits 1.1 inches lower than the sedan, effectively using the same ride height as the S4 and A5, and it gets a front and rear track that is about a half in wider than that of the sedan.

The rest of the story is pure A4/S4 narrative. The A5 Sportback is powered by the same turbocharged 2.0-liter 4-cylinder that makes 252 horsepower and 273 pound-feet of torque. The engine sends its thrust through the same 7-speed dual clutch transmission to the same Audi Quattro all-wheel-drive system that has a standard 40/60 front/rear torque split and can send 70 percent of the power to the front or 85 percent to the rear. Unlike the A5, however, it doesn't offer Quattro Ultra, which can disconnect the front axle under light load conditions to preserve fuel.

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The S5 Sportback is motivated by the same 3.0-liter turbocharged V-6 as the S4 and it makes the same 354 hp and 369 lb-ft of torque. It gets the same 8-speed automatic, and again Quattro is standard. It also offers the same S Sport package that features a mechanical torque-vectoring rear differential, red brake calipers, and sport-tuned adaptive dampers. Like the S4, buyers can also opt for an active steering system with variable ratios that range from 10.5:1 to 25:1, depending on speed, instead of the standard 15.9:1.

2018 Audi A5 Sportback

2018 Audi A5 Sportback

2018 Audi A5 Sportback

2018 Audi A5 Sportback

2018 Audi A5 Sportback

2018 Audi A5 Sportback

On the road, all that hardware makes the A5 Sportback a sporty, well-balanced, smooth-riding car with just enough power for a luxury grand tourer. The 0-60 sprint takes 5.7 seconds, and the 7-speed dual-clutch transmission shifts quickly though with a bit of lumpiness. The car rides well on its standard 18-inch wheels, and provides frisky fun through corners.

The S5 adds a bit more flavor. The V-6 cuts the 0-60 mph time to 4.5 seconds and offers a willing well of power whenever it's needed. The 8-speed offers smoother, quicker shifts, and the adaptive suspension makes the ride with the optional 19s as smooth as you get in the A5 Sportback with its 18s. The available torque-vectoring rear diff really aids the handling, too, enhancing the car's neutral, rear-drive character by dialing out any understeer. 

Should you buy it?

The A5/S5 Sportback easily earns its place in the A4/A5 lineup. The lines are coupe-like but not as sexy as those of the A5 coupe, and with less real estate to play with, they aren't quite as graceful as they are on the A7. However, this is still a good-looking car, and it delivers utility, too. The back seat might be a bit harder to get into than the sedan's, but the headroom and legroom are close, and the cargo space is a clear win for the Sportback.

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All this comes at a bit of a premium. The A5 Sportback starts at $43,575 compared to $40,375 for an A4 with quattro and $43,775 for an A5 coupe. Basically, versus the sedan, you're paying $3,200 for a C-pillar, a wider track, and the convenience of a hatchback; you actually save a couple hundred bucks compared to the coupe. That seems like a pretty good bargain to me.

However, I would be inclined to pony up the $55,375 for the S5 Sportback, which adds not only 102 horsepower, but also a sport suspension, bigger front brakes, heated front sport seats with a massage function, leather and Alcantara interior trim, full LED headlights, front and rear parking sensors, and blind-spot monitors. I'd also add the $2,500 S Sport package for the adaptive suspension and torque-vectoring rear diff. With that configuration, you get a good-looking, sporty, and quick car that can carry four adults and their luggage comfortably.

Seems like a niche worth exploring to me.

Audi provided travel and lodging to Internet Brands Automotive to bring you this firsthand report.