If Monte Carlo had a sister city, would it be Sin City? Glitzy condo canyons, matte-red Italias parked in no-parking zones, lots of places named "Palace," and an ample supply of two-name celebrities like Roger Moore, Gina Lollobrigida, and Ringo Starr--yup, it all kind of hangs together there, karmically.

I take pleasure in leaving both places, too. In Vegas, it's the existential thrill of you don't have to come back voluntarily. In this cheese-wedge-sized portion of the principality of Monaco, the pleasure spools out by the kilometer, on the roads draped in herringbones between the quaint 5000-square-foot cottages of the rich and famous. Seriously, it's like the world's most prestigious summer camp up there.

Last week, I got to leave Monte Carlo, and come back, and do the same thing about four or five times. And for a nice change on a European adventure, no times were in the company of five different layers of bureaucracy.

This time I did it in the company of the 2015 Audi S3, the hot compact sedan that's coming out swinging for the Mercedes-Benz CLA45 AMG. It won't officially be on sale until summer of 2014, but the S3 is in previews now, as the theater types would say.

Once I could stop making jeu Monegasque references, I dug into those hillsides and darted between those ultra-wealthy crash pads like I was casing them. Careening from Place Du Casino to an even happier place, the S3 proved out my working theory that Audi probably could make a crisp, warm baguette fun to drive, if they could figure out a way to put a transverse powertrain and quattro in one.

Pitch nearly perfect

The S3 comes from the new A3 family of cars, which land ashore next year in the U.S. in all sorts of body styles. There's the sedan, an Avant wagon, a pretty convertible, and a plug-in hybrid hatchback all to come--and we'll throw in the compact Q3 crossover, which isn't as precisely related to the others, but close enough for short attention spans. Audi's new compact cars will go on sale about six months after rival Mercedes-Benz launches its new 2014 CLA 250 compact four-door and its 355-hp CLA 45 AMG companion piece and the GLA crossover, which it totally lumps together with the others.

With the A3/S3 cars, Audi is resetting the clock to 1994, when the first A4 sedan inaugurated name changes and niche shifts across its lineup. Sized like the VW Golf and part of VW's massive global "MQB" family of transverse-engine compacts, the new A3/S3 sedans are close in size to the first A4. Yes, that's how much cars have grown over the past two decades, people.

But here's the twist: While the other A3 variants get turbodiesel fours, turbocharged fours with as much as 220 horsepower, even plug-in hybrid technology, the S3 blows it out with a high-boost version of the new group 2.0-liter turbo four. Power output hasn't been officially translated to SAE standards, but the S3 should be good for about 290 horsepower, and for a 0-60 mph time of about 4.8 seconds--a performance benchmark just two-tenths of a second shy of the CLA 45 AMG, which sports almost 60 more horsepower.

The new powerplant's a chummy piece. Its torque peak of about 280 pound-feet comes low--just below 2000 rpm--and sails through 5000 rpm unabated, always brapping and chortling out a happy soundtrack. There's ample torque available at just about any speed or in any gear. It pulls terrifically through the dual-clutch transmission, snicking from gear to gear at the touch of a shift paddle, just the way we like it.  Quattro all-wheel drive is standard.

All A3 sedans bound for the U.S., by the way, are supposed to come with the six-speed, dual-clutch transmission. It has one fewer gear than the CLA's seven-speed unit, the extra cogs hardly are missed, what with two or three usable gears always at hand. If you must whine, whine at Audi: they teased us with a six-speed manual transmission on the first drive, and are making some friendly noises toward the save-the-manuals crowd. It would set the S3 apart from CLA45 AMG, at least.

The S3, by the way, runs on a transverse-engine architecture, with a strut front suspension isolated on its own subframe, with a four-link torsion-beam rear suspension used for efficient packaging. It sits about an inch lower than the coming A3, and has a stiffer front structure and suspension tuning to handle the higher cornering loads. Electric power steering is standard, and selectable: the rack's variable effort is controlled by Audi's Drive Select system, which rules over the usual auto, sport, comfort, auto, and dynamic modes, or in the custom-choice individual mode.

Ever since we drove the RS 7 earlier this year, we've been more inclined to try setting the cars in Individual, and leave everything in Dynamic save for Auto damping--which the S3 comes with, optionally. It's a good compromise: the steering's heavy weighting works on kinky mountain roads up and down the mountain, the ones where even a compact car feels a little too big, and the ride quality balances out the upsized tire choices. In Dynamic setting, our S3's electronically controlled, magnetic-fluid dampers were a little too stiff in the knees, shod with 19-inch ContiSport summer tires as they were. It's something I might feel completely different about Stateside, as was the case with the RS 7 and even with the CLA45 AMG.

No matter: it's a good thing the Drive Select toggle switch sits up high on the dash, easily flicked to comfort or auto mode when you're off the sequential 15-mph hairpins that isolate Monaco from those royalty-slaughtering Huns to the north and west and east.


Looks, space and safety

The S3's tidy styling avoids risks, pulling off the usual Audi theme without looking too blunt or tall, which could easily happen on such a short car with such a short wheelbase. The headlamps have the now-obvious LED running lamps as eyeshadow, with full LED treatment available to turn their keyhole shape into something instantly identifiable in the rearview mirror.

The S3's cabin is a pretty spartan environment, if you're accustomed to the lush wood and leather trimming that's graced cars like the A7 or even the original A4. The leather's real here, but the VW influences are still pretty heady. To wit: those big, round vents that bullet through the dash. They're perfectly executed, with concentric circles that are not like the starred, gimbaled round vents in another car in this segment. What, are they reading off each other's papers?

The S3 gets the better of things with its pop-up LCD screen, though. The fixed, stand-up screens on the latest BMWs and Benzes are more cheaply integrated, and it shows. Not here: the MMI display rotates in and out of the dash, positively dripping color with its Google Earth maps.

As for the interior space, it's a bit of a throwback compared to today's A4 sedan. At 175.9 inches long, on a 103.4-inch wheelbase, the S3 is almost nine inches shorter than the CLA-Class, with nearly three fewer inches of wheelbase--which the Mercedes uses up with its laid-back profile, leaving lots of usable space under the glass. The Audi's marginally wider. 

It's notable from the back seat how the S3's doors and roofline make its petite back seat more accessible than the one in the CLA. Neither's a palace, even in a postage-stamp-sized principality like Monaco. I had lots of headroom, but admittedly the S3s driven weren't trimmed with the standard sunroof. At least in the S3, the base red-bolstered seats feel terrific, and complement the flat-bottomed steering wheel. The VW Group controls are hard to miss: there's a lever to raise or lower the seat, a knob to tilt the seatback.

In the back seat, there's the same lack of adult knee room as in the CLA, with easier entry and exit thanks to those regularly shaped doors. It's not a place grown adults will want to gather, but it's made more usable with split/fold seatbacks that expand the 13.7-cubic-foot trunk.

The A3 doesn't rely on body along to protect passengers. It has pre-collision restraint prep, simulated torque vectoring on the front wheels via its anti-lock brakes, and a passel of optional safety technology, including blind spot monitors and adaptive cruise control that maintains a traffic crawl with a tap of the cruise's resume button.

Now featuring not T-Mobile

Every S3 will come with standard power windows, locks, and mirrors; cruise control; leather upholstery; Bluetooth; and a panoramic sunroof.

Audi's MMI system is also standard, with that retractable screen serving as the output destination for the S3's audio and phone systems. MMI now has a wide touch surface on its controller knob, for fingertip text entry--just write out letters, Palm Pilot style, and MMI translates them into destinations or other data. The MMI interface has also been reworked slightly to fit on the S3's console: it now has toggle switches to flip to navigation mode, which conserves space.

Audi Connect will be a key upgrade for the connected class. For a subscription fee, A3 drivers can tap into a 4G/LTE data network that delivers Google Earth maps and other rich feeds to the car--which can even store photos of destinations for use as favorites. Audi Connect enables service to as many as 8 devices, and can stream music from them via local wireless networks it creates. It can all be rendered through a 14-speaker Bang & Olufsen audio system with 705 watts of output. A side note for T-Mobile fans, both of you: Audi's giving the data provider the Heisman late this year, and switching to a much bigger carrier for LTE service. You can guess which two players are in that game, right?

The 2015 Audi S3 shows up at American dealers by the summer of 2014, a few months after the $29,990 A3 sedan lands. The S3 hasn't been priced, but hints of about $40,000 have migrated up a little to something more like $42,000--which still would be a massive discount over the CLA 45 AMG's $48,000 pricetag.

Are those savings worth it, even with the AMG's stated 0-60 mph times being a half-second quicker? Or is the CLA45 AMG too pricey for a car that doesn't even have a plan for a manual shifter?

Read more about the Mercedes-Benz CLA45 AMG first drive and decide for yourself. Meanwhile, we'll be busy finding a few days in the calendar to put them back to back, sometime next spring.