You can tell quite a lot by the names car companies give to the colours of their vehicles.

The Astra pictured here might look yellow. Very yellow, in fact. Actually, it’s Sunny Melon, a quirky shade for a marque which is full of new-found optimism.

Just look at the Adam, already a contender for Car of the Year.

Or Mokka, a chunky rival for Nissan Juke and Skoda Yeti and my favourite new model of recent months. Mokka will sell by the shipload.

And the Cascada, a glamorous four-seater convertible designed to challenge Volkswagen Eos, Audi A5 Cabriolet and other luxurious open-toppers, will be a hit when it goes on sale in March.

But it’s with the relatively ordinary Astra that we kick off this year’s roadtest reports. In fact, today’s Astra is a million miles from the humdrum Astra of a few years ago.

Today’s Astra is impressive in all its forms. Hatchback is simple yet sportily attractive and the Sports Tourer is arguably the best-looking mid-sized estate car on the road.

But tested here is the coupe version, the GTC (£22,430 in test form, but costing from £19,040) which is the sexiest Astra going. I did wonder if Vauxhall would keep the ambitious lines seen on the earliest pictures of the GTC. I’m glad to say they did.

It’s lean and athletic and, thanks to a wondrous piece of engineering, the ride and handling is fantastic for a front-wheel-drive car. The test version is a 1.7 litre turbodiesel which offers 65mpg. Sensible? Yes, but in a very sporty way.

Ten seconds for the 0 to 60mph dash is quick and the top speed of 122mph is faster than you could ever need.

The ride and handling is, in fact, too good. It’s jittery and firm and, for me, it could do with a touch of softness now and again. Vision is hampered a little by huge rear pillars. But actually there is very little else to criticise.

Performance is smooth. The cabin is glorious and should be held up as an example to lesser marques to copy, managing to be both elegant, sophisticated and easy to fathom.

And while the nose couldn’t be anything other than an Astra, the boot and the rear haunches are classy.

UK versions of the GTC have been tweaked to cope with our challenging roads and our demands for cars which can corner well.

If you really want astonishing performance you could splash a little more for the GTC VRX, a 2.0 litre model which costs £26,995 and rips to 60mph in under six seconds.

For most Astra types, the 1.7 diesel is the best option. Power. Performance. And plenty of miles per gallon. As for Sunny Melon? Well, it does grow on you.