My accountant - who is (a) a very fine man, (b) a superb driver and (c) reading this - is looking for a new car. At the time of writing he hasn't decided what he will buy, but his heartstrings are being tugged mightily by the BMW 335d Coupé. And I can understand this, because I'd like one too. The choice of 3-Series BMWs is wide and in most cases very tempting, but out of the whole bunch I would go as far as to say that this is the most desirable.It's a good looker, for a start, though its shape does not mean a major reduction in practicality. Boot space is 410 litres, which is just 50 away from what you get with both the saloon and estate 3-Series (though of course the estate becomes a much better hold-all if you fold down the rear seats), and unless you really carry a lot of stuff with you that discrepancy might be a reasonable price to pay for the sleeker shape.But this isn't the main thing. The actual main thing - the jewel in the 335d's crown - is the quite magnificent three-litre six-cylinder turbo diesel engine. I'm quite a fan of BMW's two-litre four-cylinder diesel, and I'd probably recommend it over this one on the grounds of running costs and good-enough-for-the-job performance, but that's a difficult stance to maintain when you're in the process of driving a car that has the larger engine.It really is a magnificent piece of work. It produces a maximum of 286bhp, which not so long ago was about the most you could have expected from an M3. This full potential isn't realised until 4400rpm, and that's pretty high for a diesel, but it doesn't matter because maximum torque - a thundering 427lb/ft - is being developed at 1750rpm. Whatever gear you've selected for a given situation, you could probably shift up twice and get away with it.Since we're on the subject, gearchanging is a particularly simple matter. BMW doesn't offer a manual gearbox with this car, so it's six-speed automatic or nothing, but you're encouraged to take control of gear selection yourself using the controls on the steering wheel.These look rather odd. At the front there's an unsightly metal blob which you prod with your thumb if you want to change down. Changing up is achieved by using your fingertips on a flat paddle which isn't immediately obvious from the driver's seat, though to use one of the most venerable clichés in the motoring journalism book it "falls easily to hand".There is one of these blob-and-paddle affairs on each side of the wheel, so you can choose which hand to use. It's a choice I could do without, personally - on the Sequential Manual Gearbox system used on, for example, the M6, you change up using one paddle on one side of the wheel and change down using the other paddle on the other side. That's a much clearer, more satisfactory arrangement, and I'm not sure why BMW decided to deviate from it in the Coupé.I would have preferred to use the gearlever itself for shifting, but it hasn't been moved across the centre console in the conversion to right-hand drive, so it's too far away to add to the enjoyment of sporty driving.Whoa, timeout. Sporty driving in a diesel with automatic transmission? Even when we're talking about a BMW Coupé? Really? Why, yes. In all its forms the 3-Series is an uncommonly well-balanced car, partly because of its weight distribution. Virtually the entire engine lies between the front and rear axles, so the fact that the 335d's turbo diesel is heavier than an equivalent petrol unit would be means that the suspension is not as badly compromised as it might be.Audi mounts its diesels ahead of the front wheels and has to work its socks off to rescue the handling situation. More often these days than before, it succeeds, but BMW's engine location policy saves its suspension designers the hassle right from the start.It's still possible to get things wrong - I'm no fan of BMW sports cars, for example - but the 3-Series is generally right, and the 335d Coupé is one of the best examples in the range. Although the low-profile tyres and sports suspension do the ride quality no favours, the situation isn't too bad, and in any case this behaviour is redeemed by the handling. The car sits well on the road, reacts to the surface rather than against it, and quickly takes up an attitude in mid-corner which sees it ready for as much power as you can throw at it.Could it be any better? Well, it could if the steering was right. In other 3-Series models there isn't a problem here, but in the 335d Coupé the steering is much heavier than it needs to be. Turn the wheel a couple of degrees off-centre and it feels as if you're manoeuvring a slick-tyred racing saloon in the pit lane (this, in case you were wondering, is not a compliment). A more fluid steering action would be a better match for the splendidly fluid way the car deals with corners.Apart from that and the gearchange system, though, there's little to complain about. The 335d Coupé is smart, fast, quiet, refined and purposeful. Not especially cheap, admittedly - if your budget means that a list price of £35,475 isn't a problem, fair enough, but if it's a stretch then I would return to the point that the two-litre diesel is an excellent, if less interesting, alternative.Bear in mind, too, that the list price is only the start of the matter. Our test car had enough extras to take it above £41,000, and some of them are well worth considering if only for their effect on resale values. The navigation system at £1970 and the Dakota leather upholstery (replacing the standard cloth trim) at £1295 certainly come into this category.Rear parking sensors are part of the basic package, and you may as well pay an extra £285 for a similar system at the front. But, if you'll excuse me repeating a point I've made several times before, I still can't get my head round the fact that BMW charges £75 for floor mats. What is the world coming to? Engine 2993 cc, 6 cylinders Power 286 bhp @4400 rpm Torque 428 ib/ft @1750 rpm Transmission 6 speed semi-auto Fuel/CO2 37.7 mpg / 200 g/km Acceleration 0-62mph: 6.1sec Top speed 155 mph Price From £36361.00 approx Release date 23/09/2006