This is a bit more like it. The petrol-engined B-classes we’ve tried have been less refined than we’d expect and more expensive than they should be. Now, in the week that the B-class goes on sale, we’ve got into a diesel version – the B180 CDI.Don’t be fooled by the name, this ‘180’ is actually a 1991cc turbodiesel with a lazy specific output of 54bhp per litre. Its 108bhp, developed at 4200rpm, is coupled to 184lb ft of torque developed between 1600 and 2600rpm, and it’s this figure that gives the best clue to the engine’s nature. Although it lacks outright power and is vocal at low speeds (though imperceptible when cruising), it’s one of the most driveable four-cylinder diesels around. Throttle response is good, there’s little lag and no surging when the turbo spools up in the manner that afflicts many modern diesels.The standard gearbox is a six-speed manual unit, which is mechanical and precise in feel. Its usability, however, is blighted by the location of reverse gear - back and to the left on a dog-leg. Although that’s not a problem in itself, the lock-out mechanism means you have to lift the lever to select reverse. Fine in left-hand-drive markets, but a particularly awkward action with your left arm.Engine and ’box aside, this B-class is much like the others we’ve tried. Spacious and refined, with loads of rear legroom, a decent ride and competent, albeit uninvolving, handling. And like the other Bs, it’s also too expensive at £18,995 in basic trim, or £19,945 for the SE tested here. Standard specification is respectable, but this sort of money buys faster, better equipped and equally spacious cars.