As for the rest of the Model S experience, that's a bit of a revelation, too. Performance wise, think BMW 5 Series with warp drive. Our test car sports the bigger 85kWh lithium battery and it really shifts.

Some independent tests have measured zero to 60mph at four seconds flat and it feels good for that sort of performance. With the battery pack entirely contained on the floor of the chassis, the centre of gravity is bonkers-low, too, about the height of the wheel hub.

Tesla Model S

So the Model S corners super-flat and absolutely doesn't seem like the two-tonne beast that, in fact, it is. It's also rear-wheel drive and really feels like it. Toggle off the traction control and there's drifting for the digital generation on offer.

Overall, the dynamics are up there with the very best in the industry. For the most part, this is not a car you have to make exceptions for based on its novel pure-electric drivetrain.

Open range

The final piece of the puzzle for any electric car involves range and recharge. Our day with the Model S started at Tesla's service centre in Acton, west London and began with a 40 mile round trip up and back the M40 to familiarise ourselves with the car.

After returning to base, we headed out again, via the M4, to Newbury, squirted up and down the leafy lanes, stopped for some photography and the returned to Acton during rush hour.

Tesla Model S

It was a pretty mixed bunch of driving, little of which was executed with range conservation in mind. We just drove the car as we would a conventional combustion powered alternative.

After all that – around 175 miles - the Model S still had an estimated 75 miles left in its batteries. Not far off, in other words, the typical 100-mile overall range of most electric cars.

All of which means the Model S is genuinely usable as proper transport. OK, it's still not a true long-distance vehicle in the UK. At least not until Tesla gets around to installing a promised network of super chargers.

Tesla Model S

Using existing public charging facilities, topping up the massive battery is the work of around 15 hours. At home it could be double that using a standard wall socket. With one of Tesla's super chargers, you can half fill the battery or add 150 miles of range in just 30 mins.

But in many ways, talk of charging times misses the point. For us the model usage for the Model S is a bit like a mobile phone. Charge it overnight and use it during the day. With a 300-odd mile range, the Model S gives you more options for doing that than just about any other electric car.

What's the catch?

At this point, you might be thinking we're blown away by the Model S's all-round attributes. And for the most part we were. But there are a few niggles.

Performance of the infotainment system aside, the general ambience of the cabin doesn't quite tally with what is expected to be an £85,000 car. The Model S feels low rent inside next to similarly priced saloons from, say, Audi or BMW.

Tesla Model S

There's more noise on the move than we expected, too. Silent running is one of the attractions of an electric car. But the truth is, when cruising on the motorway it's wind and road roar suppression that matter and the Tesla is nothing special by those metrics.

Then there's the £85,000 price itself. Yes, cheaper models with smaller batteries will be available from around £55,000. But even that is a hefty sum and for us the 310-mile range of the biggest battery is central to the Model S's overall appeal.

Tesla Model S: Verdict

The Tesla Model S is far from perfect, then. The infotainment system can be sluggish. Some parts of the interior feel cheap. Noise suppression on the motorway is nothing special. And the asking price is pretty painful.

But it's what the Model S does well that makes much more of an impression. The huge 17 -inch touchscreen is a revelation and has permanently altered our view of what makes for a great in-car multimedia system.

Tesla Model S

The Model S's exciting dynamics and impressive real-world range are also game changers when it comes to conventional perceptions of what electric cars are capable of. In many ways, the Model S makes almost every other car on the market seem suddenly a bit last century.

Deliveries of the first right-hand drive Tesla Model S cars are expected early next year with prices starting at around £55,000 for the smallest 60kWh battery offering 240 miles range and extending up to £85,000 for the 85kWh performance-pack option with 310-mile range and the quickest acceleration.