Any accusation that Mercedes-Benz is trying to confuse customers with its numbering system can be swiftly rebuffed. The B-Class is exactly what it says it is - a midway point between the still radical A-Class and the rather more conventional C-Class.
A midway point in terms of size and price, at least. In concept, it's much closer to the A-Class, and indeed looks quite like an extended version of it, though with a curious hint of the Chrysler PT Cruiser about the front end design. (I know that Mercedes and Chrysler are part of the same company, but surely this is mere coincidence.)
The B-Class also shares its little brother's twin-floor arrangement, whereby the engine and gearbox slide underneath the passenger compartment in the event of a really stonking front-end shunt. That may not sound like much fun, but it's better than having them reduce your shins to matchwood.
The twin floor means you sit higher in the car than you might expect from the exterior shape, but although this means there is slightly less interior space than might otherwise be the case the B-Class is still very roomy. There's plenty of room in the front, and bulkier rear passengers are aided by the indents in the back of the front seats, where they can put their knees.
Luggage space is impressive, too. There's 504 litres of it with all the seats up, and much more with them down. The test car was fitted with the £205 Easy-Vario option, which lets you remove the rear seat backs and dispose of the front passenger seat altogether. This gives a potential 2205 litres of cargo room, along with the ability to carry a 2.54-metre object (of exactly what nature I can only imagine) without having the tailgate or any of the windows open.
Another option, and - at £1390 - by far the costliest on the car we had, was continuously variable transmission in place of the standard six-speed manual gearbox. This knocks half a second off the 0-62mph time, but we're talking about the 109bhp CDI turbo diesel here and nobody is going to buy that for searing straightline performance.
In any case, the small deterioration to 11.8 seconds is mostly accounted for by the CVT's way of moving the car gently from a standstill. You just can't rush this even if you wanted to. Once the B 180 is up and running, though, it doesn't seem to suffer in terms of acceleration.
And this is in any case a very fine example of CVT technology. There are six ratio holds which you can select if you really want to (didn't see the point myself), and the transmission will also select them itself when it feels the need. Going down a steep incline, for example, it will notice that the car is accelerating with no input from the driver, or maintaining speed when the brakes have been lightly applied, and very usefully lower the gear ratio to provide engine braking.
The B-Class is significantly more expensive than most other compact MPVs, the idea being to provide a quality option within the category. It certainly feels more high-rent than its approximate rivals, though it lags badly behind them in one respect.
Mercedes has not been shy about fitting various electronic aids to assist in the event of what pilots call an "intensely interesting" moment. This is a good thing, but it does nothing to make the B-Class enjoyable to drive. For all the marketing claims that about impressive driving dynamics, the B 180 CDI at least is notable for its lack of them.
In a class stuffed full of cars whose manufacturers have brilliantly overcome the issues relating to a high centre of gravity, this one is disappointingly lacking, with a ponderous ride and no great enthusiasm for changing direction. The second point may be related to the very long wheelbase, which also contributes to a wide turning circle and makes parking something of a chore in tight environments.
Without any extras fitted, the B 180 CDI breaks through the £20,000 barrier by £185. The test car was worth £23,240, mostly thanks to the CVT and the Easy-Vario seating system. Other options included telephone pre-wiring with a hands-free facility (£400), a panoramic fixed-glass sunroof (£440), myrtle wood trim (£200) and metallic paint (£340).
If you've been paying very close attention you'll realise that the sum isn't quite complete. The remaining £80 is accounted for by the Seat Comfort package, which provides height adjustment, cushion angle adjustment and lumbar support on both front seats (the driver's one has height adjustment as standard).
Of all the extras Mercedes supplies for the car, this must be by far the most cost-effective, and as someone who finds it difficult to get comfortable behind the wheel I'd recommend it with great enthusiasm.
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