There might be mild hybrid-diesel versions of Mercedes' latest mid-size SUV, the GLC, but it seems that Mercedes has set its sights on the fleet market. The big news is there are petrol and diesel PHEV versions available. As such, it's no surprise that the petrol plug-in hybrid version - the GLC 300e - was the first model we got to drive. 

Outside, the GLC is all-new, although you'll have to double take, as apart from changes to the frontal design bringing it into line with its bigger Mercedes SUV brothers, it looks much the same. 

Underneath the new bodywork, the GLC 300e is powered by a 211hp, 2.0-litre petrol turbo engine combined with a 95kW electric motor, and large 31.2kWh battery, equalling an impressive 381hp. While the performance of the GLC 300e will raise eyebrows, company car drivers are going to be more interested in the 5% BIK charge, emissions as low as 12g/km, average economy of a scarcely believable 565mpg, and the fact that this Mercedes can travel 80 miles on electric power alone. Although, on the cold wintery day that we drove this Mercedes, the best we could do was just over 60 miles. 

Rated at 11kW AC charging capacity, the GLC 300e can be fully charged by a wall box in two and a half hours - although the lack of fast-charging ability seems a bit of an omission, in our opinion. 

Inside, like the standard GLC, the GLC 300e's dashboard is dominated by the latest MBUX infotainment system, with its iPad-like screen curving out of the centre console. An impressive system, based around personal profiles, you sign in when getting in the car, notifying the GLC of things like the preferred driving position and radio station. Unchanged from the S and E-Class models, like them, the graphics are top quality, and despite all the features it is simple to use. The updated 'Hey Mercedes' voice recognition system, seemed to work better here - or maybe it was just us? It is a shame then, that the excellent augmented navigation display obscures the whole screen when making direction changes - this can add to the daily heartache if you don't know where you're going. Why couldn't it be integrated into the head up screen? 

Like modern Mercedes models before it, the overall feel of the GLC's interior is tasteful, spacious, and high-quality - whether you travel in the front or back. In fact, the biggest compromise to this GLC's practicality is the boot space, which is shallower and drops 200 litres to 400 litres, thanks to the battery being underneath.

As you'd expect, this GLC automatically defaults to electric mode, so there is no engine noise as you press the start button, with it only switching to petrol power at higher speeds. Hybrid mode feels much the same. Overall, the GLC 300e is best described as refined and comfortable, but not at all sporty even with our test car in AMG-Line Premium Plus trim. The GLC 300e drives best with charge in its battery, although sometimes the engine and electric motor don't always feel in-sync, equalling some less than smooth transitions between the power units. Plus, the nine-speed automatic gearbox sometime feels like it's searching for a gear for too long. Sport mode works with the engine only, doesn't feel any faster and the added engine noise seems at odds with this GLC's relaxed feel. 

That heavy battery adds significant weight to the GLC, which you can feel with lots of body roll in corners and some body float on undulating roads. Although even with the standard 20in wheels fitted to our test car, this GLC rode well in general. 

The only other driving disappointment with the GLC 300e, are the brakes which lack feel and are hard to modulate - although the re-gen works well.