I guess this is subjective. Personally i like the constant on better because during stop and go cell phones in particular never get a full charge when the ignition gets turned off.

Secondly; it not a good idea to leave devices plugged in on a regular basis. Law enforcement discourages it because of the invitation to thieves.

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"What you hear in a great jazz band is the sound of democracy. “The jazz band works best when participation is shaped by intelligent communication.”
Harmony happens whenever different parts get to form a whole by means of congruity, concord, symetry, consistency, conformity, correspondence, agreement, accord, unity, consonance…….