Topless supercars have come a long way since Lamborghini first chopped the roof off a Diablo, transforming it from merely sketchy to highly suspect. Back then, convertible versions were just a means to hoover up dumb money, a nod to buyers just barely more likely to take a V12 sports car to its limits than arrive in the south of France without a base tan.But things are different now. Open-top supercars are serious machines with technology up the wazoo (Or is that out the wazoo?) But is Lamborghini's flagship version up there with the most rarified of the über-roofless? We found out.

( Lamborghini wanted me to drive the Aventador Roadster so bad that they flew me to Miami to test it on track at Homestead, and down on South Beach's Ocean Drive and Collins Avenue. There, I learned the British mafia has relocated to Miami from Marbella, due to Spain's extradition treaty with the UK. We don't have one of those. Maybe they've already placed their orders.)

Ka-boom. The Aventador launches out of a corner with the intensity of a primordial fireball birthing a planet that would yield a car that accelerates with the same intensity as the primordial fireball that birthed the planet and eventually the car itself. BOO-YAH. Eat it, Clarkson.

That's the self-confidence the driver of an Aventador Roadster should project, not necessarily while caning it on a racetrack (we'll get to that), but definitely while creeping along the bikini-teeming promenades of Miami Beach. With the roof panels removed, and fully enveloped in the glow of Italian Supercar, you're not just some schmuck with a bad haircut and an off-the-rack shirt. You're a 24-carat demigod, scrooching down from his heavenly platform to deign the riffraff on Ocean Avenue with the heady exposure of his splendiferousness.

"Get in," the demigod seems to say to the sun-kissed maiden standing at the curb who, for good measure, is also making the O-face. "And lose the bikini."

Oh right, the car. It's easy to forget what job you're here to do when Lamborghini sends you off in the Land of LeBron with such curb-wattage. But we're also concerned with the car's massive power and often-puzzling driving dynamics, too. Remember, this thing is wide as a goddamn Chevy Suburban, has a Haldex driving the front wheels, and produces enough torque to slide tectonic plates around like lunch trays. The upshot is, it's a handful to drive, even with great steering.

These days, super marques like McLaren and Lamborghini are taking their open-top sports cars seriously, building carbon-fiber monocoques that provide good torsional stiffness even when the top's down. Prior to that, convertibles — with no top to stabilize the frame — were prone to twisting in opposite directions, making them a compromise at best and like driving a wet dishrag at worst.

Lamborghini started with a stiff, forged composite frame, and added structural bolstering (carbon-fiber, of course) at the rocker panels, which adds nearly 110 pounds. Moreover, unlike some targas, the removable tops do provide some stiffness. Without doubt, the chassis is light-centuries more rigid than that old Diablo's, and undetectable from the Aventador coupe, at least without some twisty rig that has a meter on it.

The downside of those carbon-fiber roof panels — though they're only 13 pounds each — is that they're only a hair less cumbersome to put on and take off than the T-top panels on a '78 Camaro. They've got a pin-and-latch system that binds the two together without a central support, and a novel bracket system in the forward cargo compartment makes storing them fairly painless.

And yet, both Ferrari and McLaren offer automatic tops, which are fine for the plebes who drive those econoboxes. Everyone knows Aventador drivers, who will shell out nearly a half-mill for the Roadster, all told,have people on call to take care of their roof panels for them. Storage? Are you nuts? Who doesn't have their stuff forwarded? Get frickin' real.

Still, there's nothing in the world like hearing, al fresco, that massive Italian V12 do its best to liquefyyour skull with succulent noises. Maybe this is what kite-boarding in a typhoon, while on fire and eating an In-N-Out burger, is like.

And yet, amid all that opulence and resplendency,the Roadster gives a wink toward emissions control. A new cylinder deactivation system halves the engine's volumetric capacity when cruising on the highway. It's also got a stop-start system that cuts the engine instead of idling at stoplights, then fires it up instantly using supercapacitors instead of a battery. (A demigod's car should have no less than supercaps.)

In sum, the Aventador Roadster is not a choice if you're looking for the most acute driver's car, unless you happen to live at one end of a runway, and there's a Miami nightclub at the other end. Then, the top Lambo's explosive acceleration and 217 mph top speed (even with the top off) will make every day of your very strange, opulent, nightclubbing, runway-living demigod's life like a dream.

Lamborghini's delivered more than 1,200 Aventador coupes since last year, and with the roadster expected to account for a majority of sales, it seems like demigods make good customers.

It's a Lamborghini flagship. It exudes menace, it's inspired by science fiction and it comes in colors that could fry a naked cornea at 30 paces.The major difference between the Aventador coupe and the new Roadster happens at the engine compartment cover. There's a curious central spine, flanked on both sides by diamond-shaped openings with pairs of hexagonal windows that look like a lighting fixture from the 1960s Italian avant-garde. Or Blade Runner. The purpose is cooling, draining rain water and showing the engine.

Also, the Dione rims — 20” front 21”rear — look dopesauce.

The electronic TFTdash cluster, bright and full of promise like an Eton grad, makes me giddy with anticipation. The seats are comfortable, though could use a bit more bolstering for the track or canyon carving (stop snickering), but are perfect for a night out. Also, remember how, in that old Diablo your butt and the steering wheel felt like they were in different time zones? No so in the Aventador.

If the Bugatti Veyron didn't exist, the Aventador may have squeaked a 10 in this category. The way the Aventador explodes out of corners, or down any straight — using launch control or by just hammering the gas and hanging on like Rollie Free's underpants — is a vicious, animal experience. Blowing through five hammer-to-the-skull shifts in Corsa mode, with that normally aspirated V12 wailing like the White Lady of Sorrow, then seeing the incongruously large number on the speedo — that's the core entertainment value of an Aventador.

In Corsa mode, the super-aggro throttle mapping makes it feel like an on-off switch. Sport mode sets a more progressive throttle feel, and also sends 90 percent of the power to the rear wheels, so that extra throttle control comes in handy.

I'm not saying the Aventador is overbraked, but when you hit the pedal, which is heavy and progressive with proper bite, aircraft freeze mid-sky.

Naturally, the Aventador Roadster uses the same inboard, pushrod suspension fitted with the same Ohlins coilovers as the coupe. The difference, Lamborghini R&D and motorsports boss Maruzio Reggiani explained, is that the spring rates have been adjusted, adding a bit of softness. Probably to ease the strain on rarified behinds. That's good for ride quality along the avenues, but not the best for track performance.

What a perplexing car to drive. This thing is wide, heavy, super-powerful and has a torque peak at 5,500 (and relatively flat leading up there). Do you pick Corsa mode, which delivers a 30-70 percent front-rear torque split? That requires disciplined attention to corner entry speed, but when you get the rotation to happen (sometimes by unsettling the car and letting the diff reel you in) you're off and gone in a matter of no time. In Sport mode, you can engage a bit more fun-time countersteering, though the ESP is a little more apt to step in, and the more progressive throttle mapping makes the fuel supply easier to control. It's not an easy car to drive, so its fun can't be derived by tossing it into a corner, seeing what happens and then throttling out, but by setting up, waiting and launching madly into the wild.

There's no doubt the Aventador's rod-actuated automated manual is a marvel of packaging. More than that, on a racetrack, in Corsa mode, those infamously engineered-to-be-violent upshifts do initiate a pull of testosterone with each head-smashing, racecar-mimicking click of the paddle shifter. But roll out to Collins Avenue with an expensive date, and — while Strada auto mode is far better than Lambo's old e-gear for cruising — stay off manual, or the low-speed jerkiness will make that open bottle of Ace of Spades erupt, undermining the impact of your floodlit arrival at Insert Name Of The Club Where LeBron Did That Thing.

Wait, there's a stereo? Crap. Did I mention there's an Italian V12 carving you out a new ear hole? It's Audi's system; it's probably fine.

The Aventador gets the "trickle-up" electronics from Lamborghini's Audi parent, which supplies the nav system and MMI interface. That way, the Aventador doesn't suffer the same e-neglect to which other supercars are prone. Also, thank you rear camera — this thing would be a bitch and a half to maneuver without it.

Ok, here's the tough part. How do you judge the value of a car you could easily spend a half-mill on. That's a half-million dollars — the price of two McLaren MP4-12Cs, eight BMW M3s, 20 Fiat 500 Abarths or a 4,000 square-foot home in Austin, TX.

Look at it this way. With an Aventador — spitballing here — if you figure you're getting around 60-70 percent of the performance, technology and curbside appeal of a bespoke hypercar like, say, a Koenigsegg Agera R or Pagani Zonda — at around 30 percent of the price, then the value proposition looks pretty favorable.

If, say, you're looking for the perfect driving experience, you could just buy a Porsche 11 GT3 and 1000 track days, or a Ferrari 458 (if you're allowed) and half than many track days.

But c'mon. That Porsche doesn't have an Italian V12 — an increasingly rare mechanical aphrodisiac — and even in the Ferrari, dozens of onlookers won't whip out their camera phones to Instagram shots of your science-fiction thriller car as you roll past, and tan, bikini-clad women won't volunteer to dance in the street, and no one will ever mistake you for British mafia.

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