My general impression of the BMW 7-Series still contains some elements which can be summed up in a couple of words, those words being "too much". However, there's no denying that this is a highly superior car, built by a company whose opinions about exterior styling may be different from those of a lot of other people, and which doesn't shy away from complexity, but really knows what it's doing when it comes to engines, dynamics, materials and quality control.And yet, the look of the 7-Series is beginning to seem less frumpish than it did at the start, perhaps because more of us have accepted that it's a matter of simple shape rather than any kind of ornamentation.In any case, BMW isn't about to make any apologies for the latest model range, and doesn't need to, from the business point of view. The first full-year sales figures contain some remarkable statistics. In 2002, which was by no means a good period for luxury car sales, the 51,000 cars sold worldwide represented a 4% increase on the corresponding launch-year figure for the outgoing model, which found another 2500 buyers in its run-out year.And while we're quite used to German cars in this sector having the US as their top market and their home country second - which is the case with the 7-Series - it's a mind-boggling fact that the number three market is China. The new breed of Chinese businessmen and entrepreneurs have taken to the top BMW as enthusiastically as their counterparts in the West.BMW found 1755 customers for the new range in its first year on the UK market, which it entered, as you might say, with one hand tied behind its back. As we mentioned in our original launch report of the new 7-Series, only the V8-engined 735i and 745i were available here during 2002 - no six-cylinder petrol models, no turbo diesels, and no sign at that time of the V12 760i and the phenomenal long-wheelbase 760Li.Also in the original launch report, we said that, of the two turbo diesel versions, BMW would be importing only the smaller-engined 730d. The 740d is still reckoned likely to be too expensive, but there's nothing to get crotchety about. The difference in performance isn't all that great, and the important thing is that there is now, for the first time since the series number started to be used, a diesel 7.Outwardly - well, either you like the look of the 730d and its stablemates or you don't. Side-on the styling is very effective, front-on it's something BMW fanciers are gradually coming to terms with, and at the back it does seem a little clumsy in places.Inside, the 730d shares the now better known 7-Series fascia layout, instrument array, electronic parking brake, trim materials and general design. It also features the formidable iDrive system, which confuses some first-time users. At the original international launch, BMW didn't want any of the scribblers to start off in the car without a ten-minute explanation of how iDrive works. Many of us nodded knowledgeably as 95 different things were explained to us, but pottered off having taken very few of them in, then stopped up the road, out of sight, and started raking through the handbook.The complexity is still all there, but if you're into electronics, telematics, communications and a powerful rush of information, as so many motorists in this sector are, then iDrive is an admirable partner. And it does, with time, become easier and more logical to use.However, while the 730d has so much in common with the rest of cars in the 7-Series catalogue, the obvious question is: does this model hack it as a luxury saloon? There's no doubt at all about the answer. The 730d is a splendid machine.First of all, the three-litre engine produces 369lb/ft of torque from 2000rpm, and that translates into excellent low and mid-range pull. The 730d is a tremendous hillclimber, and it can dart into very swift overtaking manoeuvres, helped by the top-class throttle response.Then, although there are circumstances in which there's no hiding that this is a turbo diesel, however sophisticated, the overall noise levels are commendably low. In particular, BMW has tuned out road noise to the point where it's hard to believe, on a good motorway surface, that there's anything going on as normal as tyre treads pressing down on tarmac. Wind noise is also restrained, and - of course - it's the lack of both that and road noise which makes the sound of the engine tend to come through when it's accelerating hard, or on the over-run.As a second-generation common rail design, the six-cylinder 730d engine - the most powerful unit of its kind in its class - doesn't just benefit from improvements in its injection system. It's also lighter, has an uprated management system and a swifter-responding turbocharger.A six-speed automatic transmission, with Steptronic buttons on what is a rather large steering wheel, is standard. So is a sophisticated cruise control system. Anti-roll bars are fitted front and rear, there's firmed-up suspension in the Sport version, and the 730d is certainly not kitted out as simply a motorway cruiser.The result is a car which, as well as the comfort features of its petrol equivalent, offers vivid performance and excellent economy for its class, and relaxed high-speed cruising. Thanks to its CO2 figure, it's also the most tax-efficient model in the whole 7-series catalogue. BMW is offering it in three different specifications, all with the same powertrain. The SE comes at a £2000 premium over the standard version, with the Sport on sale at another £2200 on top of that. They're all in the same insurance group. Engine 2993cc, 6cylinders Power 218bhp @4000rpm Torque 369ib/ft @2000-2750rpm Transmission 6 speed auto Fuel/CO2 33.2mpg / 227g/km Acceleration 0-62mph: 8sec Top speed 146mph Price From £45191.00 approx Release date 01/03/2003