Perspective is an odd thing. You'll probably either view the Mercedes B150 as a very inexpensive Mercedes or a very pricy mini-MPV. The £18,840 asked for the car isn't a whole hill of beans in Mercedes terms, but it places it up against some very competent rivals, all of whom have a lot more going on under their bonnets. Do you trade bhp for badge equity or should you give the B the bird? In order to make an informed judgement, let's take a closer look at what you're getting.

The first thing that will strike most observers is how much bigger the B-Class is than they expect. Pictures seem to show a chunkily compact little thing, but despite the fact that the B150 is a few millimetres shorter than a Ford Focus, it's tall and reasonably wide. It also tips the scales at 1,300kg which is why the 95bhp engine struggles to move it with any great alacrity. Load the car up with passengers and luggage and performance and economy take a real hit. The trouble is, if you want a car that can haul this amount with reasonable go and which won't drink like a fish, you'll need to fork out another £2,000 for the B180 CDI diesel, a hefty undertaking by most standards.

Mercedes quote a sprint to 60mph in 13.2 seconds and a top speed of 108mph for the B150, the 1.5-litre four-cylinder engine sounding a touch thrashy towards the red line. Drive the car a little more responsibly and you should be able to see 42.8mpg on the combined cycle although few will be able to replicate this figure. The engine is rare in offering only two valves per cylinder and the rather paltry torque figure of just 140Nm means that you'll have to downshift if you're to make decent progress up long motorway grades.

In a bid to further drive down emissions and save fuel, buyers can now opt for a B150 BlueEFFICIENCY model which features an ECO start/stop function. This generates fuel savings of up to nine per cent in city traffic, the engine cutting out when the vehicle shifts to neutral at low speeds while depressing the brake pedal. A starter-generator fires the engine back into life far quicker than a conventional starter motor.

Although the engine isn't anything to get excited about, Mercedes have come a long way in developing compact car chassis since the days when the old A-Class fell over in the 'elk test'. The B-Class handles tightly and competently, with perfectly placed pedals, very good body control, keen turn-in and brilliantly optimised electronic control systems.

"If the raison d'etre of the B150 is to highlight how good other B-Class models appear, it can be deemed an unqualified success"

Keener drivers may complain about a slight lack of steering feel and fidgety low-speed ride but this is a far better handler than most would give it credit for. Even the basic architecture of the car does a lot to keep the centre of gravity low. There's far less body roll than you may expect for such a high-sided vehicle. With a little more weight to carry around than the equivalent A-Class, the B150 enjoys decent front end traction, although the 95bhp rarely troubles the traction control system.

Mercedes has worked to sharpen the appeal of the B-Class and the unassuming front end now looks a lot more purposeful thanks to revised headlights and grille. The rear styling has also been tidied up and there are now no models that don't sport body-coloured mirrors, door handles and skirt panels. The B-Class has always been more about the inside than the outside though. Sit in the back of a B150, stretch your legs out and you'll appreciate that it's comparable with the amount of room in the back of an S-Class limousine. Only those at the extreme end of the ergonomic scale will have any problems with head or legroom and there's ample room for three abreast. Despite this, the B-Class breaks the tape at only 4,270mm long. To put that figure into perspective, a Ford Focus measures 4,342mm from bumper to bumper, making this Mercedes something of a packaging marvel. So why aren't we all beating a path to our local Mercedes dealer?

The big caveat for many will be the asking price. Yes, we're used to Mercedes charging a premium, but at £18,840 (for either SE or Sport variants), you've got to really want one in order to sign the dotted line. Although many will look at these prices, compare them to something like a Renault Scenic or a Focus C-MAX and decide that the gulf is just too large, the B-Class doesn't purport to be a mini-MPV, instead targeting family buyers who would have previously bought something aspirational but practical. Vehicles such as Volkswagen's Passat Estate, Saab's 9-3 Sportwagon and Volvo's V50 would sit squarely within this category. That's the Mercedes take at least.

Mercedes dub the car a Compact Sports Tourer, but despite the great strides in driveability made by the A-Class upon which the B-Class is inspired, 'sporty' is perhaps a stretch too far. Still, although it won't make the cover of evo magazine, the B150 is nevertheless a decent steer. And a practical one. The rear seats all fold flat into the floor and the boot floor can even be raised to offer a flat loading surface. Other clever touches include a front passenger seat that folds forward to permit long loads and slots next to the rear doors to allow seat belts to be stowed safely out of the way when loading and unloading. The centre rear seat back can also pop forward, offering an armrest with a neat pair of cupholders when travelling four-up. The driving position is undeniably sporty. The wheel sits almost vertical and your legs stretch forward into a deep footwell. It almost feels like sitting in a jacked-up Lotus Elise but for the interior quality.

In order to best appreciate the great strides Mercedes have made with the B-Class, acquaint yourself with, say, an old A-Class or an early M-Class model. Open the glove box and observe how the hinges look only marginally more expensive than a CD case. Pull at the floppy plastics of the lower dash. Marvel at how Mercedes had the chutzpah to put a plastic gearchange selector in the M-Class that wouldn't pass muster in a Kia. The B-Class isn't quite back to the over-engineered Benzes of the Seventies, but it's as good as anything else out there in terms of perceived quality. Not only that, but the interior aesthetics are, to this eye at least, a lot happier than those in the latest BMW and Audi offerings.

The dashboard is cleanly designed with a neat mix of contrasting colours and metallic detailing. Standard specification across the range includes air conditioning, a four-spoke steering wheel with multifunction buttons, an armrest between the front seats, electric windows and tinted glass, plus brushed aluminium trim on the fascia, transmission tunnel and door panels. Front parking sensors should have made the list too, as the front of the car slopes rapidly away and the body-coloured rubbing strips don't look as if they'd withstand too many scrapes with a concrete bollard before they started to look a little secondhand.

The Mercedes B150 would appear to be a car contrived to give the B-Class an attractive lead-in price. Most things unique to this model aren't particularly noteworthy and the B180 CDI, although £2,000 more expensive, would seem a far better buy. There's a lot to admire about the B-Class but just not this particular car.

TOP 4 B CLASS DEALS

The results below show the top B CLASS deals on buyacar

	Mercedes-benz B Class B150 SE 5dr CVT Auto Hatchback
	ETR	Mthly £353	Saving £1,458	Price £18,797
	Mercedes-benz B Class B150 SE 5dr Hatchback
	ETR	Mthly £323	Saving £1,333	Price £17,502
	Mercedes-benz B Class B150 Sport 5dr Hatchback
	ETR	Mthly £321	Saving £1,333	Price £17,502
	Mercedes-benz B Class B150 Sport 5dr CVT Auto Hatchback
	ETR	Mthly £351	Saving £1,458	Price £18,797

typical 11.76% APR

PCP finance quote over 48 months,  10,000 miles pa,  deposit of £1000