San Francisco is famous for its summer fog. We natives have even named it Karl. The fog can roll in out of nowhere, turning a warm, sunny day into a sub-60-degree chiller.

But Karl's easy to deal with in the 2018 Mercedes-Benz E400 Cabriolet. Hit the Airscarf button and your neck is wrapped in warm air. Roll up the windows and the Aircap system uses an A-pillar extension and mesh windscreen behind the rear seats to channel cold air up and over the cabin.

Karl can't ruin my top-down fun. And that's before you get to the other reasons why the new E-Class Cabriolet is a seriously delectable droptop.

Comfy cruisin'

While the E-Class Sedan is offered with a wide array of engine options, the Cabriolet makes do with just one: a 3.0-liter twin-turbocharged V6. (That is, until the AMG E53 Cabriolet arrives.) This V6 produces 329 horsepower and 354 pound-feet of torque, with smooth shifts from the nine-speed automatic transmission.

The E400's Comfort drive setting is a perfect match for this turbo V6 and nine-speed auto combination. The Cabriolet has soft, plush handling characteristics befitting of a proper grand tourer, and in this default mode, the entire behind-the-wheel experience is easy like Sunday.

Sport allows for slightly flatter cornering and quicker changes of direction thanks to its improved steering response, and while the ride is definitely stiffer, it's still perfectly compliant over rough pavement. Sport+, meanwhile, turns the E400 into a high-strung, twitchy thing. It feels like it's trying too hard to turn the E-Class into a performance car, with its more aggressive throttle and transmission programming, when really, this is a total cruiser.

An advanced suite of tech

When I get into dense San Francisco traffic (the only thing denser than the fog), I'm happy the Mercedes is loaded with features to make commuting easier.

Adaptive cruise control effortlessly follows the car in front of me and can bring the E400 to a complete stop. It'll even change speeds based on local signage, though this function can also be turned off if you wish. Steering Pilot smoothly keeps the car centered in its lane, and heck, the car will even change lanes itself. If adaptive cruise and steering assist are both enabled, all you have to do is flip on the turn signal and the car will take care of the rest.

Inside, the E400 Cabriolet uses Mercedes COMAND system, with a pair of 12.3-inch screens that make up the gauge cluster and central infotainment display. The result is a widescreen format that offers better in-car tech than just about anything else in the class.

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COMAND can be operated by a dial on the center console or with small thumb pads on the steering wheel. Some folks will complain about the lack of touchscreen functionality, but personally, I prefer this setup. Touchscreens tend to make me take my eyes off the road for slightly longer than I'd like.

The COMAND system itself is relatively easy to use, though there are a lot of menus and submenus within those menus. Happily, Apple CarPlay and Android Auto offer a more straightforward experience, and both come standard.

Top-notch comfort

COMAND is just one part of what is a truly stunning cabin. The big screens are placed alongside gorgeous, open-pore wood, and stylized, retro-chic air vents. Combine that with rich leather on the seats and door panels, and a wonderful attention to detail with the metal finishes, and you have an interior totally befitting of the three-pointed star on the E400's grille.

The E-Class seats four, though the back seats should be reserved for smaller passengers. And while a lot of convertibles are noisy, the E400 is nicely hushed. Wind and road noise are kept outside thanks to the heavily padded soft top, which can raise or lower in 20 seconds, and at speeds up to 30 miles per hour. Depending on your exterior color, you can even have the roof fabric done up in red, black, dark blue or dark brown.

How I'd spec it

The E400 Cabriolet starts at $66,300, and if you want 4Matic all-wheel drive, add $2,500 to that base price. The optioned-up car you see here costs $85,735 all in.

For my money, I'd stick with rear-wheel drive since I don't need the assurance of 4Matic on mostly dry California roads. I'd shell out $950 for the massaging seats because, as they say, treat yo'self. I want all the advanced driving aids, too, but I hate that you can only get the full suite as part of the $9,350 Premium 3 package. To that, I'll add $450 for ventilated seats and $1,050 for the heated-everything Warmth and Comfort package. In the end, my E400 Cabriolet comes out to $78,045, including $995 for destination.

A class of its own

As far as competitors go, there aren't many that stand toe-to-toe with the Mercedes. You could get a BMW 430i Convertible or Audi S5 Cabriolet, but those are smaller, competing more with Mercedes' C-Class range.

Really, think of this E400 Cabriolet as a cheaper alternative to the bigger S-Class convertible. Like the flagship S, this E-Class excels at comfy cruising, and doesn't hate being pushed on twisty back roads. The onboard tech is some of the best in the class. And with comfy-cozy features like Airscarf on hand, it's the sort of convertible you really could drive every day.