The Model S is billed as a mid-size four-door sedan, but in fact it's a five-door hatchback, with a pair of optional rear-facing jump seats in the load bay that offer nominal seven-passenger capacity. To be fair,
Tesla bills the Model S as a seven-passenger vehicle. We contest the seven-passenger claim—those seats are suitable only for children of age eight or so--and their occupants may chafe at the four-point safety harnesses they'll have to wear. Still, no other sedan this size even tries to hold seven occupants. That's been the province of large crossover utility vehicles (Tesla's planning to offer one of those, too).
But the hatchback convenience and large size deliver lots of comfort and significant cargo capacity for families, with massively lower operating costs than equivalent-sized gasoline vehicles. Inside the Model S, the cabin is wide, and five adults should be able to travel in comfort.
The driving position is good, the front seats are supportive, and most controls are well-placed. Rear-seat passengers will find the door openings smaller than they look, and the windows slope inward as they rise toward the roof rail. That makes access to the rear seat more challenging than expected, though it's comfortable enough once you're inside.
The outboard rear passengers are likely to notice that that the cabin is wider at shoulder height than at head level and the rear seat back is angled a bit more steeply than customary. And if the Model S has the panoramic sunroof, a six-foot person in the rear seat comes within a fraction of an inch of the headliner. But most adults should be comfortable riding in the rear over long distances.
The 2012 Tesla Model S has a slightly different seating position than every other luxury sedan, since it's the only one with its battery pack in the floorpan. That makes its front and rear foot wells shallower than in cars without 5 inches of battery beneath passenger's feet. Rear passengers especially sit in a more reclined, knees-up position than in competing sedans from Audi, BMW, Jaguar, or Mercedes-Benz. It's not necessarily uncomfortable, but it is noticeable.
On the road, though, the Model S is so calm and quiet that there's essentially no mechanical noise on acceleration. Only once, on full acceleration from 0 to a high number, did we hear a high-pitched humming whine--presumably from the power electronics. Tire noise is obvious with the stereo off, and then wind noise kicks in above 40 mph or so.
There are a few quirks behind the wheel. Tesla has used column stalks from Mercedes-Benz (which owns part of the company), with both an upper cruise control and a lower turn signal, meaning that Model S drivers will try to signal with the cruise lever until they retrain themselves. Mercedes-Benz owners will be very familiar with that problem.
The wheel has a tilting and telescoping adjustment, and to the right of the column, a drive selector offers simply D, R, and P. Tesla uses an automatic electric parking brake, but it activates automatically in Park when the car senses that the driver is getting out.
Total interior volume of the Model S is rated at 95.1 cubic feet. There's 26.3 cubic feet of cargo space in the rear load bay with the rear seat up, and a total of 58.1 cubic feet with the seat folded down. There's also an additional 5.3 cubic feet in the surprisingly large front trunk, which Tesla insists on calling a "frunk." It's worth comparing that total cargo space to the absurdly tiny 6.9-cubic-foot trunk of the similarly large-on-the-outside Fisker Karma, which is so small inside that the EPA rates it as a subcompact.
Early Model S cars we've seen appear to be well built, and Tesla is ramping up its assembly rate slowly to ensure that its plant and workers maintain high quality as they move into volume production. On a car within the first 125 units, about all we noticed were a recalcitrant rear seat-belt retractor and a misaligned Velcro patch on the front-trunk liner--both fixable issues.