Is the earth round? The new 7 Series BMW is a dream of a car. Sink into the cream leather upholstery of my 750i test car and you'd never want to leave. The purr of the engine, the cool air conditioned cabin, the smooth handling - all add up to a seductive package that could make you throw caution to the winds and re-mortgage your home to buy one. But let's not spoil the dream by bringing that nasty folding stuff into the equation just yet.

The 7 Series is first and foremost a luxury car, so male or female, if your career is on the up and up, you would surely feel you'd made it when you acquired one. However, your family would also enjoy the fruits of your success in this spacious saloon. Think of that long, hot drive to your summer cottage - the children would be cool and comfortable in the back, while you and your partner would soak up the miles listening to your favourite music on the marvellous CD player. You would all arrive frazzle -free, feeling that your holiday had already begun. The boot is cavernous, so no heated discussions about the girls leaving half their wardrobe behind. There would be plenty of room for favourite toys just in case the weather turned nasty and you could even stock up with provisions to save wasting time at the village store when you could be on the beach. Bliss.

Much has been written about BMW's novel i-Drive system, designed to eliminate dashboard switchgear. Much of this has been negative, mainly because those concerned don't seem to have bothered to read the handbook. So let's get this straight: i-Drive makes sense. After all, this car has so many functions that if you gave them all a switch, the dashboard would look like the cockpit of a 747. Besides, the current 7-Series features a less complicated version of the system. Many of the more commonly used controls have been relocated out of the computer and onto the dash. Sit behind the wheel and the main i-Drive functions are controlled by a circular silver wheel by your left hand. You push it towards either of the eight positions of the compass to select all the main function areas like the stereo system, the trip computer, the satellite navigation system, the TV (where fitted) and so on. There's even a section that tells you just how much life is in all the consumable parts of the car - the brake pads and so on - and when you're going to need to replace them. Clever. You start the car with a push button and there's the option of changing gears via an arrangement of silver buttons on the steering wheel. Four petrol models are available -, the 730i, the 740i, the magnificent 750i that I tried and a range-topping 760i. Oh and a diesel 730d. Whichever version you choose, you'll find that the automatic gearbox is arguably the smoothest you'll find, either for stop start driving around town or long motorway stretches. The Servotronic steering meanwhile, (ask the dealer all about it) makes for easy handling. And if you care about these things, the 750i's engine is good enough for sixty in 5.9 seconds on the way to a top speed of 155mph which, like its boardroom brother, is artificially limited. No wonder - the ride is so quietly comfortable that you do have to keep an eye on the speedometer to avoid any embarrassing attention from the law. If you need something with an eye on economy, the 730d diesel could well appeal.

The 750i will always find room in my drive, but I wouldn't turn my nose up at either the 730d or the 740i. The price tag is less self-indulgent, all things being relative, and you wouldn't have to forego too many luxuries compared with the top of the range model. In performance terms, sixty takes 6.8s seconds on the way to 155mph in the 740i. And that same Steptronic 6-speed automatic is included, so you can exercise the engine to the full. All right, so it's a tiny bit slower from rest to sixty, but I wouldn't mind. Not a bit.