'This car is like a house on wheels," Bob Mortimer says as we climb into the new Mercedes E400. It does indeed appear more palatial than your average motor – a car so sprawling, I half expect to chance upon a billiards room and a scullery tucked away somewhere beyond the back seats. What it definitely does have is a hybrid engine that sounds so tasteful, so perfectly modulated, it seems more fitting to discuss it in terms of nose and palate.
With its handsome, square-jawed exterior and luxurious interior, the Merc is too big to feel truly comfortable; it makes me feel like a child trying to walk in her mother's heels. There is plenty of technological zip to counter its air of stately deportment: sport-tuned suspension, designed for sharper handling, and acceleration that delivers an unexpected rush of speed. It handles elegantly, and out on the motorway feels quite majestic. But heading south in the sludgy traffic of rush-hour London, it feels a touch cumbersome – even in super-throttly sport mode.
Mortimer drives a Mercedes himself. "I'm on probably my ninth S Class on the trot," he says. "It's my least favourite of all the ones I've had. It's only 15 miles to the gallon; the last one was a diesel, and you got about 34." At 37.7mpg, the E400's combined fuel consumption is vastly more impressive.
Most mornings, Mortimer drives 50 or so miles to write with his comedy partner Vic Reeves (who drives a Jaguar), but today we are roving around rural Surrey, close to his production company offices. He tells me about the live tour he and Reeves are preparing, as well as a feature film and and a new show he has in development called OAP-PI, in which "we get old age pensioners to do private investigations work". We pass under a railway bridge. "It's such a thin line between doing what we do and it just being Rentaghost. And I hated Rentaghost."
For Mortimer, the allure of the Mercedes is its space and comfort. "I've never found a better car for sleeping in. And I spend hours and hours asleep in cars." Had we taken this drive around his home town of Tunbridge Wells, he says, he'd have guided me to his three favourite sleeping spots. "Finding somewhere to sleep is really tricky these days, where it's reasonably quiet and you don't get moved on." He sleeps "more intensely" in a car: "You wake up and you get that real richness, like your blood's got thick."
Later, he shows me his own Merc. "I've got a fridge," he says, opening a cubbyhole in the back seat that's big enough to hold two bottles of Lucozade. "And night vision," he adds, gesturing at the dashboard. "You flick that down and drive via that screen." What if a fox ran out in front of him? "That's exactly what it's for. It was designed by foxes." We regard the dashboard dubiously. "I'm sure it must be safe," he says, looking unconvinced. "And it's probably the future."
The E400 may not offer a fridge or fox-endorsed night vision, but it's still a fine example of Mercedes design. There's all the space, comfort and attention to detail you'd want if you're spending long stretches in a car, whether driving great distances, or taking a nap in Tunbridge Wells.
Mercedes E400 AMG Sport Plus Coupe
Price £52,250
Top speed 155mph
Acceleration 0-62mph in 5.2 seconds
Combined fuel consumption 37.7mpg
CO2 emissions 176g/km
Eco rating 6/10
On Bob's stero Anything by Babybird
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