Audi's EV, the e-tron SUV, has been on sale for well over a year now, establishing the German brand within the electric car market and paving the way for new derivatives. The first to follow in its footsteps is the Sportback SUV-coupé which brings a little extra styling dynamism to the e-tron range.

Audi's e-tron is generally highly rated as one of the best options if you're after a premium electric SUV. Few competitors get close to the Audi's combination of practicality, realistic and usable range, equipment and reassuringly good driving dynamics. We thought it was worthy of a full five star rating, but at over £70k you'd hope so too.

With the e-tron Sportback, Audi is broadly keeping the same winning formula but is bringing in that new shape and “performance-oriented specification”. It'll be available in both range-topping 55 quattro spec (with the 95kWh battery) and entry-level 50 quattro spec (with the 71kWh battery) – a cheaper option that joined the regular e-tron line-up in August last year. Audi is charging a premium for the Sportback with prices for the 55 starting at £79,900, so is it worth it?

Powertrain and performance

If you're familiar with the regular e-tron then the powertrain's stats won't come as much of a surprise to you as they are common with the Sportback. In the Audi e-tron Sportback 50 quattro this means 308bhp and 398lb-ft of torque, split between two motors – one on the front and one on the rear axle. Audi hasn't given us the performance stats as it's due for sale in the autumn, after the range-topping 55, but the regular e-tron 50 does 0-62mph in seven seconds and has a top speed of 118mph.

Audi also hasn't provided the official range stats for the e-tron Sportback 50, however given that it shares the same 71kWh battery, comprised of 324 prismatic cells in 27 modules; it should manage at least 190 miles – on par with the regular e-tron 50. Charging at a maximum of 120kW will juice from zero to 80 per cent in just 30 minutes.

Step-up to the e-tron Sportback 55 quattro and the performance moves up a notch in all areas. Power stands at 402bhp alongside 489.7lb-ft of torque in boost mode which is available in eight second bursts. This brings 0-62mph down from 6.6 seconds in normal driving modes to 5.7 seconds in 'S' mode. Top speed is 124mph.

Range is similarly improved thanks to the larger 95kWh battery which has a total of 36 modules (nine more than the lower-spec 50). This affords it a WLTP range of 241 miles in S Line and Launch Edition specification, or 237 miles in Vorsprung spec (details below). With a maximum input of 150kW the 55 can be charged to 80 per cent in 30 minutes.

In both the 50 and 55 quattro cars the 50:50 weight distribution provides good balance, aided by standard five-link air-sprung suspension with controlled dampers. Ride height can be varied by up to 76mm depending on the driving requirements, and air suspension adjusted for comfort or sport. Audi has carried over the high level of energy recuperation to the Sportback, which is capable of harvesting up to 30 per cent of range through deceleration events. At its maximum regenerative setting the e-tron in 55 guise can pull back 221.3lb-ft and 295bhp of power, with the disc brakes only coming into play at over 0.3g of deceleration.

Trim levels and technology

Audi is releasing the e-tron Sportback in three trim levels – S Line, Launch Edition and Vorsprung. It'll come as no shock that even in base S Line spec the car comes with generous helpings of kit. As standard, exterior enhancements include 21 inch alloys, matrix LED headlights with front and rear dynamic indicators, as well as that standard adaptive air suspension. Cruise control with lane departure warning and rear camera-enhanced parking are standard.

Inside, all models get Audi Virtual Cockpit, a touchscreen MMI Touch system with dual monitors, wireless smartphone connectivity via Audi Smartphone Interface and wireless charging. Audi Connect is also standard, and brings with it a host of web-based functions and over-the-air upgrade potential. All of the major infotainment and control functions, such as voice control, are powered by Audi's (very good) MIB 3 modular infotainment system.

Step up to the Launch Edition and on the outside there are some design details, exclusive 21 inch alloys from Audi Sport and virtual door mirrors. A full-length panoramic sunroof lightens up the interior, and the driver gets powered steering wheel adjustment and the more sophisticated virtual cockpit plus with additional 'e-tron' and 'sport' screens providing more comprehensive driver information.

On top of an already comprehensive list of driver aids, the Launch Edition gets a 360-degree camera which feeds into everything from the adaptive cruise control through to parking assistance, collision avoidance and blind spot monitoring.

Step it up to the top-spec Vorsprung model and the wheel size increases to 22 inches – complete with matt titanium finish – with orange brake calipers behind. Powered door closure adds a bit of additional luxury and once inside, a heated steering wheel, 19-speaker Bang & Olufsen sound system and upgraded super sports seats complete the premium feel.

In all cars there's a 20mm reduction in rear headroom, but luggage space is still a decent 615 litres (including the 'frunk') with the seats up and 1665 litres with them down.

Availability and price

The 55 spec car is available to order already with prices starting at £79,900 on the road for the S Line. Step up to the Launch Edition and you're looking at £85,900, with the Vorsprung level car topping out at £95,100. If you're holding out for the 50 spec car you're going to have to wait a couple of months as Audi won't be selling it in the UK until the autumn. Prices will be confirmed closer to its 'on sale' date.

As to whether the Audi e-tron Sportback is worth the premium over the regular e-tron rather depends on how much you care about the SUV-coupé styling – as realistically that's the only significant difference. The e-tron Sportback isn't going to be much different (if at all) to drive whilst 'sporty' SUVs just look gawky – trying to be something they're not. We'd save the money and take the practicality and better resolved styling of the regular e-tron.