Let’s get a few things out of the way first. I can’t remember the last time I sat in a mainstream (or premium) upper-medium car where the interior A-pillar cover was bare plastic and not covered in the same fabric as the roof lining.

Despite its upmarket looks, the lower seat panel next to the transmission tunnel in our Optima 2 Luxe test car is leather. But it means that a driver a little heavier than me could cause it to rub against the plastic trim on the transmission tunnel and make an annoying squeaking noise.

And the stitching in the leather-covered steering wheel is the ‘baseball’ type pattern where most cars in this bracket now offer finer, more sophisticated stitching.

So that’s it. These three items that amount to serious nit-picking on my part are the only problems I can find sitting behind the wheel of Kia’s new upper-medium sector challenger.

This sector of the market has a higher percentage in fleet than any other and is fiercely competitive, with the domination of the likes of Ford, Vauxhall andVolkswagen challenged by BMW and Audi.

Kia and sister brand Hyundai, as well as Skoda, used to be able to offer a budget-priced alternative that might have fallen short of rivals looking at driver appeal or perceived quality.

This is no longer the case. The Skoda Superb is firmly established as one of the best cars in its class – twice a Fleet News Awards winner – while the latest Hyundai i40 Tourer has rattled a few mainstream upper-medium estate cages with its all-round ability.

Arguably one of the most elegant cars on the road, the Optima uses a 136bhp version of Kia’s 1.7-litre diesel engine (as found in the Sportage) with stop-start as standard (not available on auto), with CO2 emissions of 128g/km (auto: 158g/km) and fuel consumption of 57.6mpg (auto: 47.1mpg).

The Optima feels a little sharper on the road than the mechanically-similar Hyundai i40, and surprisingly nimble for a large car. The entry-level Optima 1 and the Optima 2 Tech with smaller wheels will probably offer a little more comfort on poor road surfaces than the Luxe we tried, and the 1.7-litre diesel feels a little flat below about 1,800rpm.

As the six-speed gearbox is optimised for fuel economy, it’s pretty easy to catch that flatspot when changing up.

However, the Optima is an incredibly good effort on the part of Kia, and joins the latest Sportage, Picanto and Rio as ominous markers that its products should now be taken very seriously.