We spent a week with the 2021 Mercedes AMG E53, and this is what we thought.

When the first straight-six internal combustion engines were produced, the Wright Brothers had just made their first flight and Mark Twain was still penning life's complexities. Today, some-117-years later, the straight-six (or inline-six as it's sometimes referred to) still proves to be a smooth, powerful, and soulful way to turn petrol into smiles. At least, that's the case with the 2021 Mercedes AMG E53 4matic Coupe and its 3.0-L I6 heart of gold. 

For the uninitiated, the straight-six engine design has nearly perfect primary and secondary engine balance resulting in a significant reduction in vibration. That means they're wonderfully smooth operators, make wonderful sounds, and are a great performance platform. With a little AMG-turbo-magic and a little help from Mercedes EQ boost, they're enough to start a religion.

With that said, the 3.0-Liter I6 and 48-volt hybrid system of the 2021 E53 produces a smooth 429-horsepower and 384 lb-ft of torque accompanied by a soul-soothing grumble not found in other modern vehicles. Sprint to the next corner, firmly depress the brake pedal, downshift a gear or two, relish in a symphony of revs and pops, and clip the apex with physics-behind speed—that's what this car is all about. And for people like me, that's what life's about.

Of course, in the correct mode, the exhaust is quieted down to golf-course-acceptable levels and the car remains perfectly polite at low speeds. Often times high-performance vehicles are jerky, touchy, or loud at low speeds, not so with the E53. It's even great in the snow, thanks to winter tires and Mercedes' 4matic all-wheel-drive system. 

Inside this racer-in-disguise, the plush, well-appointed interior is similar to other Mercedes models, and that's a very good thing. But the luxury appointments are more than skin deep. The tech makes it a great long-distance bruiser. More specifically, the adaptive cruise control w/active lane assist worked exceptionally well on rural stretches of long, straight interstate. As you might imagine, everything else met the standard of lux and build quality we've come to adore and expect from Mercedes. 

From a day-to-day standpoint, though, the sedan is likely a better choice, but then you lose the ability to roll down the front windows as well as the small windows behind them for that "no post," open-air feel. Our test model also came with a massive panoramic moonroof adding to its summer-time appeal, so if you really don't use your rear seats often we'd say it's worth opting for the coupe.

If there's any way to improve the E53, it's to make it more hardcore. It has the composure. It has the brakes. It has the acceleration. This car is just an ultra-fast-shifting transmission and a few decibels-worth of exhaust note away from being a proper sports car. Leave the lesser 362-horsepower E450 for those looking for a flashy quick grand tourer.

Still, the E53 remains a joy to drive in nearly every situation. For those who only have room for one vehicle or just want to add a little bit of thrill to their lives, the $86,460 sticker on our test model seemed well worth the price. Just make sure you leave it in "Sport+" with the exhaust setting in "Powerful," and never look back.