WHAT'S the most protracted car name ever? Take a deep breath and welcome the Renault Megane Sport Tourer GT Line Tom Tom Energy dCI 130. With a name as long-winded as that they'd need an extra-wide boot if the full name were attached to it.

First introduced at the 2008 Paris Motor Show, the Sport Tourer was the fifth member of the Megane family. Earlier this year it underwent a mid-life revamp - principally a Clio-style nose, projector headlights and LED running lights - to help it keep up with the competition and bring it in line with the rest of the Renault range.

More usefully, a new stop and start ignition system has helped reduce fuel consumption by up to 25 per cent (depending on the model) and slashed exhaust emissions meaning the 2014 Sport Tourer is the most cost-efficient so far.

ON THE ROAD: GT Line models borrow the sports suspension settings from the Megane Coupe.

The springs are stiffer and the centre of gravity is lower so there's less roll. The trade-off is a slightly harder ride.

Power steering is responsive and the car responds crisply. The six-speed gearbox has the same slightly vague movement that's common across the Renault range.

Inside Renault’s engineers have moved the pedals further apart so there’s no chance of hitting the accelerator when you want the brake. This may sound counter-productive if you’re a heel ‘n toe wheelman but how many would-be racers buy a C-segment estate?

The brakes are firm and progressive with good retardation from high speeds.

Although the 1.6-litre dCI is the most powerful 1,600cc diesel powerplant in the world the Megane is more ‘Tourer’ than ‘Sport’. It’s quick, but the laidback chassis feel (even in the GT Line) encourages a more relaxed driving style.

Wind and road noise is well suppressed at 70mph. The Megane cruises in near silence with plenty of performance in reserve.

ON THE INSIDE:

Renault has stretched the Megane chassis for the Sport Tourer.

This has had the effect of increasing the rear seat leg and knee room which is among the best in the C-segment class.

The driving position is good. The sports driver's seat has lumbar, fore-aft and height adjustment while the sporty steering wheel adjusts for height and reach. Strangely, the instruments are positioned at an angle. They look as though they are advancing up the panel toward the windscreen rather like the credits in a Star Wars movie. Unfortunately, 60mph isn't marked so you have to keep a close eye on your speed.

Renault has expended a lot of time and money improving the quality of its cabins. The soft-feel grained plastics and sensible switchgear have trickled down from the larger (and no longer available in the UK) Laguna model.

WHAT DO YOU GET: As well as the suspension tweaks, GT Line models add 17-inch wheels, ‘dark chrome’ exterior trim, a Renaultsport leather steering wheel, two-tone Renaultsport seats and an impressive Arkamys 3D sound audio system which uses sophisticated acoustic modelling and split-second sound delay to create a more immersive soundstage.

The latter is often dismissed as snake oil by real hi-fi buffs but Arkamys designed its algorithms  around the Megane’s interior, not a notional front room, with the result that it really does conjure up a 360 degree ‘surround sound’.

Naturally, the Tom Tom model features a bespoke version of Tom Tom’s latest satellite navigation software that boast real-time speed trap alerts (not available in France) and Europe-wide traffic hold-up information updated every three minutes.

Note that these services are free for three months after which you pay a modest annual subscription.

HOW PRACTICAL IS IT?

The Sport Tourer is a big car. Thanks to a wheelbase stretched by 62mm compared to the Megane hatchback it's longer than a Golf or a Focus both of which adopt a more practical (ie boxy) approach to their derrieres. Incredibly, the Sport Tourer is 6cm wider than a mid-1990s Ford Mondeo estate. With the rear seats in place the boot volume is 486 litres.

The 60/40 split rear seats fold down to extend the load area to 1,567 litres. Every model is fitted with a front folding passenger seat ,so you can slide in items up to 2.55 metres (8ft if you're old-fashioned like me) long and still get the hatchback closed. Loading heavy items is easy thanks to a hatch which opens down to bumper height, but you need to be careful not to scratch the paintwork.

A semi-rigid boot divider helps keep fragile items safe - handy for preventing bottles of wine rolling around on the way home from the supermarket. The roller blind luggage cover can be stashed away in its own compartment behind the rear seats when not required.

RUNNING COSTS: The 1.6 just misses out on the 100g/km CO2 figure that exempts cars from road tax. Renault claims the 1.6 is capable of 70.6mpg but the real-world figure is closer to 60mpg which is still a good result.

VERDICT: Better-looking than the determinedly Germanic Golf and the rather dull Focus, the Megane Sport Tourer is a frugal, comfortable and practical family hold-all. Recent changes have brought it bang up-to-date and the GT Line additions add a dash of sporting style.

And with a boot almost as long as its name, the Megane Sport Tourer makes a lot of sense if you need a useful family car that doesn’t cost a fortune to run.

Spec: Engine: 4 cyls, 1598cc, diesel turbo Power: 129bhp @ 4,000 rpm Torque: 236 lb/ft @ 2,000 rpm Top speed: 124 mph 0-62mph: 9.8 seconds Fuel economy: 70.6mpg (official combined figure) CO2 emissions: 104g/km Equipment: Electric windows, automatic wipers and headlights, central locking, credit card keyless entry and ignition with starter button, 17-inch alloy wheels, dark chrome exterior trim, Tom Tom satellite navigation, cruise control with speed limiter, six airbags, trip computer, USB connection, air conditioning, folding door mirrors, tinted rear windows, sport chassis with lowered suspension.

RENAULT MEGANE SPORT TOURER GT Line Tom Tom Energy dCI 130 Price: £22,245