Some years ago I has a 3500 V8 P6. Without doubt the most comfortable car I have every driven. On a long run it did 25 mpg (imperial), but only 15 mpg around town.
It had very sophisticated suspension, with a de-dion rear axel that was anti squat, with horizontal front springs connected via 90 degree links that were aranged in an anti dive setup. A supereb handling car, but very heavy which made it a very safe car. someone ran into the back of mine, while I was stationary, at 35 mph! His car was a total write-off, mine had a bent bumper and boot lid!
Wonder if there are any good ones left?