All the excellent qualities of the C-Class with A-Class-beating economy.

Price: $115,698 as tested.

Powertrain: 1999cc four-cylinder petrol with 150kW/320Nm and 95kW electric drive assist with 25.4kWh lithium ion battery, rear-wheel drive, nine-speed automatic, fuel consumption 1.5 litres/100km.

Vital statistics: 4686mm long, 2020mm wide, 1444mm high.

We like: Smooth, silent, response … and a real sipper.

Not so much: Same money will buy a like-sized full electric with decent range and near-comparable quality (if not the same badge kudos).

CUTTING back consumption is a primary goal for all plug-in hybrids, but only a special few demonstrate almost outright aversion for pump fuel.

Such frugality seems to be packaged into the Mercedes Benz C350e, the plug-in hybrid version of the sedan line.

 It’s stunning for lean-ness and CO2 output, and not just during the period I was driving it – a time when no particular effort was put into leaning out the litres.

 A delve into its whole-of-life data was revealing. The numbers suggested the test car had been a consistent thriftmeister since Day One of New Zealand driving duty.

 Would you believe that, of the 2271 kilometres’ on the odometer, just 626km had been on petrol, including the time spent with me? Yup, I had to double check, as well. It’s an amazing result.

Basically, of its total driving history – which in total time came to two days 10 hours and 59 minutes on the move – fully one day, 21 hours and 38 minutes had been dedicated to abstinence. Average consumption for all that time came to a piddling 3.7 litres of petrol per kilometre. Alternately, it drew down on 14.3kWh per 100km of electricity.

A habit reflective of the habitat it primarily been in? Prior to heading to my Manawatu turf, the car had been primarily running in urban environments, mainly in Auckland, a touch in Wellington. But not exclusively.

Before it came to me, it spent time with a colleague who works in the Queen City, but commutes from Hamilton. That involves a fair sway of open road driving, as much as I undertook with the car when picking it up from Wellington then subsequently returning it there in a stint that, in its entirety, added 550 kilometres’ clocked.  

The outcome of that certainly did not blemish the car’s good character; if anything it probably just added extra shine.

Fuel consumption averaging at 7.9 litres per 100km (3.5kWh per 100km) for the entire week was nowhere near the official optimal, which just reflects how different lab test conditions, even when designed to replicate actual driving environments, really are a stretch. Yet the car’s burn rate nonetheless made it a touch more frugal than the C200 – which runs a surprisingly zesty but also, with an official cited optimal of 6.9L/100km, parsimonious 1.5-litre petrol - tested earlier in the year. Benz’s testimony of it being able to deliver 100kms’ pure electric running was also found to be solid.

All that the car demanded in return was a degree of diligence in keeping the battery at good state of charge and plugging in frequently. But even when it was in driving scenarios where a big effort from the electrical drive was demanded, it did sterling work; prioritising battery drive even at steady 100kmh for considerable distance.

When the state of health finally dropped to a couple of bars, it almost begrudgingly allowed the 2.0-litre engine to involve, and even then purely in a hybrid capacity. I cannot think of any time during my test when it ran on petrol alone, at least not in the economy mode.

It’s a different story in Performance. But, while car feels almost indecent in that setting – fast enough to hit 100kmh from a standing start in just over six seconds - it kinda defeats the purpose of what it aims to achieve. Frankly, too, it feels quite potent enough in normal driving scenarios in the eco setting that to shift from those is just being showy.

When you drive a Mercedes Benz, you do tend to expect it to deliver a high degree of technical competency among the qualities associated with the badge, and the C350e certainly sets a high standard among PHEVs by including two key features which are typically found purely on electrics wholly dedicated to battery driving: ‘one-pedal driving’ and DC fast charging.  

The first, when in its most active regeneration mode, is especially useful when negotiating heavy traffic or slow road conditions. The vehicle actively slows as soon as the accelerator is released, effectively acting as a brake, with the dual benefit, Benz attests, of reducing driver fatigue while also generating maximum energy recuperation.

The second just means it will not only get the best out of the 50kWh chargers that are still the most powerful points of replenishment for much of NZ, but also that you won’t spend a lot of time at those places. Taking the car back to full state of battery health from around 25 percent took 40 minutes.

The performance, the manner in which in runs and the easy living involvements cumulatively make it one of the better PHEV choices in the luxury part of that sector, and you’d think Benz would be happy to rest on those laurels.

What’s more remarkable, then, is knowing that the car here now is a stepping stone. While it would quite adequate to keep in circulation for say the next five years, in likelihood it might have been overshadowed by then. 

Benz has already decided that a fully electric sedan of similar size with tech from the super-efficient Vision EQXX concept could be on the road by 2024.

The currently unnamed car will be the first to be released as the first under the marque’s "entry luxury" branding on an upcoming modular architecture platform, conceived for small and mid-sized EVs. At around 4.7 metres long, will essentially provide Mercedes with a long-awaited executive EV to rival BMW i4, Polestar 2 and Tesla Model 3.

That’s the expected, because Benz’s line-up of electric models already comprises a wide variety of cars of different shapes and segments – everything from EQA to EQS, and soon to include an electric G-Class - and there’s a commitment to develop only bespoke EV architectures from 2024. 

Potential it’ll be an interim thing doesn’t make the C350e any less desirable in the here and now. The C200 provided just how extremely polished this current fifth generation C-Class is; the C350e simply amplifies that impression. 

Specifically, of course, that’s in respect to the performance and the equipment level. From a broader view, a C200 and C350e impress equally in respect to the design and the dynamics.

Argument that Mercedes’ sedans have the best premium cabins right now is surely hard to dispute. So much of this environment is an object lesson in how to design and execute a terrific interior. Though the carbon fibre effect highlights and mood lighting around the air vents might sound a bit try-hard, they’re really not over the top at all. Plus, everything is to exceptional level of quality.

 For all the technology relayed, the car’s digital displays are really easy to acquaint to. The driver display comprises a 12.3-inch screen ahead of the steering wheel. It’s impressively configurable through multiple display themes and modes. My advice is mess about with while it parked up, find a theme you like best and then stick with it. 

Thereon you can devote attention to the  centrepiece, the enormous iPad-like MBUX screen reclining on the centre console, subtly titled towards the driver by six degrees.

Having functions on a screen is hardly ever really a great idea from a driver distraction point of view; I’m still in that camp which prefers at least a few proper, physical buttons. For that reason, Mercedes having now migrated the heating and air conditioning controls to the display left me a little edgy.  However, I need not have been concerned. This high-resolution screen is, by virtue of its clear graphics, fast reactivity and intuitive menus, is by far one of the better, less perplexing layouts around.  

Again, though, you want to take a few minutes to learn it – including, of course, the displays bespoke to the hybrid drive activity. But, honestly, that’s all it takes to get the hang of the basics. Actual owners will see sense in setting up their own ID and preferred settings, using the Mercedes Me app, a process whose ultimate action involves enacting a little fingerprint scanner below the screen, as this will, from thereon, identify an individual driver and pre-loads all their infotainment and comfort settings.

 Those who aren’t sure about that or are, like me a temporary user, needn’t worry. If you’re still employing the app, the car allows much the same one-on-one personalisation bond by using a pin code which it asks for on start up. Setting up doesn’t require too many personal details. They’re not really watching you. Or maybe just a little bit. I picked up the test car on Halloween and it put devil’s horns on my profile image.

In addition to the touch screen, it has haptic controls on the steering wheel, mainly for the stereo and cruise control, but still enough to fill two of the three spokes . Is it better than the previous setup, which used a mixture of physical buttons and touch-sensitive pads? Not so sure, really.

 All the same, it’s no major quibble, and assuredly the C-Class cabin is a place of great comfort and convenience; it feels like a pukka luxury car that’s up to date in respect to tech.  

This one has optional features of a panoramic sliding sunroof ($3799) and some anthracite wood trim ($699.20), neither of which are must-haves to support the plushness. It’s loaded anyway. Wireless phone charging and equally wireless Apple CarPlay and Android Auto connection involves and it has USB-C sockets sprinkled around. In the centre console, there's a large storage area under a hinged lid, while there's more space (and sockets) under the 'butterfly' armrest in the front. The door pockets are also a decent size.

The C350e also provisions as standard with the Driving Assistance package; it’s the complete and very fulsome array of safety and driver assists that Benz delivers to its cars, including not just active assists for braking and lane change but also an evasive steering assist. Benz style with this tech is to have it sitting quietly in the background, rather than intrude prematurely. None were called into action during test.

It’s a car in which the driving position adjusts nice and low; perfect for the sporting ambience and for a tall bloke like me. Such a shame, then, that those with large feet – I’m a size 12 - will find the dummy pedal beside the transmission tunnel is insufficiently wide.

 In terms of overall cabin space, its cosy but not too tight; three kids will be okay across the back seat but, if adults are involved, it’s better for two. There are ISOFIX anchor points in the outer two rear seats, and a helpful rear-seat seatbelt indicator in the dashboard. Though the fuel tank is 16 litres smaller than standard, need to package both it and the battery for the electric drive affects boot space, it’s basically okay at 455 litres’ cited without being brilliant, but is at least square and unobstructed.

In weighing up the driving side of things, it’s less about outright fun than about outright satisfaction. Though it’s quick at kick-off, with 0-100kmh in 6.1 seconds, it shouldn’t be confused for a sports sedan. The weight of its hybrid technology can be felt on tight and twisty roads. But the car’s not without good feedback – the chassis has inherently good balance, with ability to composed even under considerable provocation - and it has decent steering feel. All in all, though, you appreciate it for it being quiet, comfortable and dignified.  Bar a touch of tyre roar on coarse chip, it's a very refined car with a relaxed gait that holds it in good stead for long distance driving.

So many hybrids are about compromise, but it’s truly hard to see where the C350e is trading off. Sure, it’s all PHEV typical in that you can tailor how the system operates, with an E-mode for all-electric driving, a hybrid driving mode and options to save battery charge or generate more electricity using the petrol engine. It’s important to learn when and how those are beneficial.

If you take the time and make the effort to maximise its electric performance, then you have a car that can for the most part glide guilt-free around town, yet still offer strong performance on the open road. Yes, that part is invariably petrol-fed, but it’s not drinking much.

The way in which the electric half of the powertrain combines with the petrol half is really good.

It’s sad there’s no longer a petrol six engine in the C-Class- the last was a paragon of engineering – or that it can longer fit out with a decent diesel, but that’s not worth dwelling on: Petrol four-cylinders are all the go with C-Class now, even the previously V8 C63 has joined that camp. The powertrain the C350e has now is an unalterable determination made in face of unavoidable realities.

The new set-up isn’t the same thing, but it is another good example of why Mercedes holds such great reputation for engineering excellence. It’s an exemplary kind of PHEV.

 There’s plenty of electric involvement and, when you're running on that alone, it’s confident and of course extra-quiet. When the petrol engine is awake, you'd hardly notice most of the time. Until, that is, you switch in the performance setting and put your foot hard down. Then it’s even occasionally snarly, definitely less saintly. But it does have a lot flexibility – 100km electric and fast charging are elements that do genuinely appeal. Being okay to tow, too, is worth considering.

An interesting car at an interesting time.