BMW's three-litre turbo diesel engine is widely regarded as being one of the finest units of its type in the world, and you won't find me arguing too strenuously against that opinion. It adds greatly to the quality of every car to which it is fitted, even including the long-wheelbase 7-Series tested here. This is a very large machine, and it's a credit to the diesel unit that it can push such a leviathan forwards with apparently minimal effort.
It's also by far the best part of the car. During my time with the 730ld I could hardly stop thinking about the long-wheelbase Jaguar XJ which I drove earlier this year (see road test) and which impressed me so deeply. The engines of the two cars are so different as to be not worth serious comparison - either you want a petrol motor or you want a diesel one - and the space available for rear passengers is comparably impressive.
In all other respects, though, I could find no reason why anyone would choose the BMW over the Jaguar. The XJ seemed to have been designed round me; the BMW seemed to want me to redesign myself round it.
An obvious example supporting this view is the notorious i-Drive system which caused gasps of horror when it first appeared in the 7-Series and had to be toned down as it filtered through to first the 5-Series and then the 3-Series.
Full review here