Autos: Mileage vs Expensing?

[Ed O.]

Over the years, it's been told to me over and over that taking the mileage deduction is better than the alternative of expensing a vehicle (forgive me if I got the term wrong.
Recently, some highly successful investors have told me they do better by expensing their vehicle.

Does anyone use the non mileage approach? Can you share under which variables it is superior to taking the mileage deduction?

thanks!