The Mercedes-Benz EQS sedanPhoto by Peter LyonMotor journalists spend much of their working lives behind the wheel.We travel around our chosen home countries and fly around the world, jump into the latest gasoline, hybrid and electric cars, drive them over mountain roads, highways and racetracks, and then attempt to explain whether they are actually any good.What we do far less often is sit in the back seat.That thought occurred to me recently as I returned to my chosen home country of Japan following a test-drive event in Australia. After a nine-hour flight back to Tokyo, a colleague and I landed at Haneda Airport needing to travel into central Tokyo rather quickly for a meeting near the Imperial Hotel.AdvertisementAdvertisementNormally, I would simply grab a cab or a train from the airport into the city and think little more about it. This time, however, as I was traveling with a colleague, and as we had been focusing our attention on the latest electric vehicles during testing in Australia, we decided to treat our return journey as an extension of our road tests, and book a luxury EV limousine, for a special kind of test.The EQS offers a smooth, whisper quiet ride.Seattle Black Limo offers luxury electric car transfersAfter all, while we test drive new cars virtually every week, we rarely get the opportunity to evaluate them from the perspective that matters most to limousine clients—the back seat—where ride comfort, refinement, quietness, rear-seat space and the ability to arrive at your destination feeling more relaxed than when you started.To get the right car, though, took a little bit of online reconnoitering . A search for an internationally connected chauffeur service led to Seattle Black Limo. Although its main hub operates in the Pacific Northwest and greater Seattle area, the company says its network extends to more than 500 cities worldwide, including Tokyo, London, Paris and Milan.That makes it a one-stop shop for frequent travelers who would rather deal with one operator than negotiate a new booking system—and language—every time they land. Seattle Black Limo offers conventional luxury sedans and SUVs, including the ubiquitous Mercedes-Benz S-Class, but through its Japanese affiliate it was able to arrange something less predictable: a fully electric Mercedes-Benz EQS sedan.AdvertisementAdvertisementUnsurprisingly, SBL offers traditional gasoline-powered luxury vehicles such as the Mercedes-Benz S-Class. But what caught my attention was that, through its Japanese partner, it was also able to provide Mercedes-Benz's fully electric EQS sedan.As expected, our bilingual black-suited chauffeur was waiting at Haneda Airport's arrivals hall holding a sign and quickly escorted us outside to the waiting EQS.From the back seat of the EQSThe EQS is surprisingly therapeuticFrom a rear-seat passenger's perspective, size matters, and the EQS certainly has plenty of it. Measuring roughly 205.4 inches long and 75.8 inches wide, the car's wheelbase stretches beyond 126 inches. That last figure matters far more because it translates into extra roominess, or more than 40 inches of rear legroom. After a nine-hour flight from Australia, the ability to stretch out in a supportive, deeply cushioned seat without listening to an engine or feeling the vibration of an internal-combustion drivetrain was surprisingly therapeutic.The transfer cost $400 in total, which my colleague and I shared. Split between two passengers, that made the experience easier to justify—particularly after a long international flight and before an important meeting.AdvertisementAdvertisementAnd the trip revealed something about electric vehicles that conventional road tests tend to overlook. EVs are arguably at their most convincing when used as luxury limousines.With its large battery mounted low in the chassis, the EQS carries much of its considerable mass close to the ground. That helps lower the center of gravity, reducing the sensation of body roll, improving stability and giving the car a planted, composed character when changing lanes or negotiating sweeping highway bends.It also remained impressively composed when crossing expansion joints and larger imperfections that are common on Tokyo's expressways. There was little vibration, almost no drivetrain noise and very little of the mechanical harshness that can creep into even expensive gasoline-powered automobiles.The EQS weighs more than 5,600 pounds, yet its electric powertrain produces around 443 hp, allowing this substantial limousine to sprint from zero to 60 mph in approximately 4.4 seconds. Not that our chauffeur had any reason to demonstrate that particular statistic.AdvertisementAdvertisementWhat impressed me more was the instant response available at ordinary highway speeds. Entering central Tokyo, the driver could place the car precisely into gaps in traffic with nothing more than a subtle squeeze of the accelerator.There was no transmission kickdown, no engine flare and no delay while various mechanical components decided what to do next.The rear seat offers loads of knee roomNo drama. Just immediate, smooth accelerationIts large 118kWh battery pack also gives the EQS the sort of range and rapid-charging capability necessary for professional limousine work. And I compliment Seattle Black Limo for showing initiative and adding an EQS to their substantial lineup.With fast-charging, substantial range can be added during relatively short stops—an important consideration for operators whose vehicles may spend much of the day carrying clients between airports, hotels and business districts.AdvertisementAdvertisementThere is another benefit, too.A luxury limousine should ideally disappear around its passengers. The drivetrain should not constantly remind you that it is working. Yes, the standard gasoline-powered S-Class is quiet in its own way, but the the EQS takes noise, vibration and harshness to greatly reduced reduced level where conversation, telephone calls—or simply staring out of the window after a long international flight—become effortless.That is where the EQS makes a compelling argument for electrification. I still enjoy the sound, character and mechanical interaction of a great gasoline-powered car. For driving enjoyment, internal combustion is far from finished. But from the back seat of a limousine, the priorities change.Quietness and refinement matters more than exhaust note. Smooth acceleration matters more than throttle drama. Ride quality, stability and serenity become the defining characteristics. And judged by those criteria, the electric Mercedes made a convincing case.AdvertisementAdvertisementIf you want to experience just how well an EV can work as a fast, quiet, vibration-free luxury limousine, the EQS is very difficult to beat.This article was originally published on Forbes.com