[brucepick]

The Prius is arguably one of the most fuel efficient cars available, and is far more quiet than most.

[Edited by poster to correct silly writing]
Do electronic [fuel injection] and the related computer control unit increase noise, vibration and harshness? I think it's generally agreed that elec. [fuel injection] is more efficient overall than carburetors. And that's without considering how carbs misbehave when they get dirty/leaky/out of adjustment.