The CSi is very much a different beast to drive compared to the 850Ci and 840Ci.
On paper, the relative performance figures don't exactly jump out at you, but I can assure you that driving it after either of these two cars was for me a life-changing event!
Having said that, I haven't yet driven the 6-speed manual 840Ci Sport (M62), which I'm told is a pretty impressive machine.
I guess the step up to the CSi is not unlike slipping behind the wheel of the E39 M5 after the very capable 540i.
But for me, the CSi just does it even more convincingly.
Not only is it a very, very fast machine, it also has masses of torque from relatively low revs so, like the E39 M5, it doesn't really matter which gear you're in, you still get that solid push in the back of your seat.
It's a big car, but as I've said previously, it just shrinks around you once you're behind the wheel.
Of course it's not everybody's cup of tea, but I'm completely smitten by this car - and that's really saying something, since my last car was a gorgeous E28 M5, itself a very satisfying, feel-good driver's car.