As I idle down the main drag through the city of Cannes in southern France, the 2017 Mercedes-AMG S63 4Matic Cabriolet looks at home among the numerous Bentleys and Rolls-Royces lining the street. And it should, because the S63 Cabriolet is itself a rather expensive piece of machinery at a $176,400 base price. My drop-top's long body sports flowing lines with a matte Allanite Gray paint job, and a tasteful amount of carbon-fiber trim to accentuate its subtle and elegant appearance.

With the French Rivera to my left and a bustling city to my right, the congestion makes the driving miserable. It's slow going, but I don't really mind too much since the S-Class' interior coddles me with its cushy front bucket seats. Since I'm testing a convertible, the top is down even though temperatures are cooler than ideal for topless motoring. Not to worry, as the S63 Cabriolet's cabin features heated seats and Benz's Airscarf neck heating system to keep me and my passenger toasty.

The lull in driving action also enables me to listen to the rocking Burmester audio system, and sift through the numerous infotainment menus on the crystal-clear 12.3-inch center media display for Bluetooth, navigation and camera systems. There's an impressive amount of stuff packed into the leather and carbon-fiber-lined interior, but being an AMG the main talking points for this car cover the go-faster and handle-better bits, which I'll soon be testing on the roads outside the city.

The S63 is handsome with simple, flowing body lines and a tasteful amount of carbon-fiber trim.

Jon Wong/Roadshow

Stop-and-go city traffic didn't tell me much about the S63's 5.5-liter twin-turbocharged V-8 engine or the seven-speed multiclutch transmission, with the exception that throttle response at tip-in lags a little. Once underway with strips of open road ahead, the drivetrain combination delivers an experience that I've come to expect from AMG models. Brutal acceleration shoots the all-wheel-drive S63 to triple-digit speeds in a flash, which isn't surprising when you look at the car's spec sheet, showing 577 horsepower and peak torque of 664 pound-feet. AMG quotes at 0-to-60 mph time of 3.8 seconds that is even more impressive given its 4,817-pound curb weight. It's evident that AMG has built yet another German muscle car with crazy straight-line performance, and a grin-inducing exhaust soundtrack that's easier to hear without a fixed roof above you.

However, the car's yacht-like dimensions and porkier curb weight don't wreak too much havoc on performance when things get a bit twisty. In fact, the S63 feels fairly sharp, thanks to the AMG-tuned air suspension that keeps things nicely tied down when rounding corners. After the initial weight transfer to the car's off-side, the S63's Michelin Pilot Sport 3 tires just grip and track through turns. Push things a little harder and the car still goes about its business with impressive composure, while my test car's optional carbon-ceramic brakes slow things down in rapid fashion. Since it's still a cruiser, steering isn't superquick to respond to inputs, and there's not much feedback felt through the wheel.

Other than the quibble with throttle tip-in response, high marks go to AMG's multiclutch gearbox that fluidly cracks through well-timed gear changes. It also features a worthy manual shift function using the aluminum steering wheel paddles.

The experience on the winding roads in southern France is eye-opening, and a testament to the solid job Mercedes has done with the S-Class Cabriolet. Benz says rigidity and body-in-white weight is on par with the S-Class Coupe, thanks to an aluminum rear floor, die-cast aluminum longitudinal support member and rear wall behind the backseats to stiffen things up. It all seems to work with no detectable body flex that contributes to the convertible's solid ride and handling traits. From there AMG takes things further with the suspension, steering and drivetrain alterations to make the S63 a respectable back roads runner.

Things settle down again in the afternoon when I get into a base model S 500 Cabriolet, which will be known here in the US as the S550 Cabriolet when it goes on sale in late spring starting at $131,400. I quickly notice its less carbon fiber-enhanced looks, lighter steering, even more compliant air suspension and quieter drivetrain demeanor. Instead of the rip-roaring AMG engine, the S 500 packs a 4.7-liter twin-turbo V-8 with only 449 horsepower and 516 pound-feet of torque. That works with a nine-speed automatic gearbox that routes powers to rear wheels.

The S 500 Cabriolet's main focus is delivering a comfortable open-top experience.

Jon Wong/Roadshow

It's definitely not as fast or sharp through bends as the S63, but the S 500 holds its own without feeling clumsy. It handles lightly spirited driving fine, and will get moving down the road briskly when you drop the hammer, but is at its best letting you enjoy the convertible experience in serene comfort. The suspension erases impacts from the majority of ruts I come across, which in combination with the light, responsive steering make it a pleasant car to wheel around.

Conversing with my co-driver is easily done with the Aircap system that extends a wind defector at the top of the windshield frame and a draft-stop behind the rear seats. Even at expressway speeds, we hear each other fine without screaming, and the lack of turbulence in the cabin keeps our hair from looking like we stuck our heads in a wind tunnel. Airscarf comes into play again in the S 500 to keep us warm.

Regular driving also let me appreciate the cabin's soft leathers, fairly intuitive infotainment interface and 23-speaker Burmester audio system. When the sun goes down, I get to try out Night View Assist Plus, which displays an image of what's ahead on the main gauge cluster and is capable of recognizing animals and pedestrians for added safety at night. My test car also features optional Swarovski crystals for the front turn signals and daytime running lights for additional bling.

The supremely comfortable cabin of the Mercedes-Benz S 500 Cabriolet.

Jon Wong/Roadshow

There are other goodies available in the S-Class Cabriolet, too, including Benz's excellent Distronic Plus adaptive cruise control system with Pre-Safe braking that uses radars to keep a safe distance from cars ahead. If the system determines that a collision is possible it applies partial braking, warns the driver with an audible tone and activates Pre-Safe to apply max brake force once the driver hits the brakes. Brake Assist with Cross-Traffic Assist helps the S-Class Cabriolet not only avoid possible front-end collisions, but collisions with vehicles crisscrossing intersections by warning drivers to brake if an impact is possible, and automatically applying full brake force if necessary. Active Lane Keeping Assist uses radar and a camera to monitor for cars in your blind spot and ones that are approaching from behind that may cause trouble if you change lanes. If a collision is possible during a lane change, the system will vibrate the steering wheel and use selective braking to steer you out of harm's way.

A couple of things that aren't available yet are Apple CarPlay and Android Auto capabilities in the S-Class Cabriolet. I'm still waiting to hear back from Mercedes to see if they have a time frame on when those features will be available.

At the end of day, I resorted to the power soft top, which works at speeds up to 37 mph and takes less than 20 seconds to turn the S-Class Cabriolet's interior into a quiet pod. The multilayer soft top seals out almost all unwanted wind and road noise, and also gives the convertible a nice roof profile, which isn't always the case with big open-air vehicles.

Which large luxury four-seater convertible would I pick to idle through the middle of Cannes again? The BMW 6 Series and M6 are tighter handlers than the S-Class Cabriolet but give up a lot in ride comfort and don't have near as nice of an interior. The Bentley Continental GT Convertible is more expensive than the Benz, and has an infotainment interface that's painfully out of date. So that leads me back to the nicely appointed and tech-rich Mercedes as my drop-top cruiser of choice. In particular, I would go with the S63 because I like corner carving, and the AMG's better handling reflexes and riveting exhaust note are just great.

If you're in the market for a high-powered convertible, have many extra bucks burning a hole in your wallet, and can wait until the end the summer, the S-Class Cabriolet lineup will add a third member with the Mercedes-AMG S65 Cabriolet. For $247,900 you'll likely have the baddest luxury open-top on the block with a massive 6.0-liter twin-turbo V-12 putting out 621 horsepower and 738 pound-feet of torque. All that power won't help you in bumper-to-bumper traffic through a city in France, but I believe the experience on a nice piece of clear road promises to be incredible and quite comfortable.