Can your current vehicle handle the drive? No, get the company car.
Yes, read on.
500 miles per week * 26 weeks * .45 cents = $5,850.
Can you operate your vehicle for less than or equal to $5,850? You'll need an oil change or two over that period and of course gasoline.
If the vehicle survives with no major problems, the amount you pocket would make a nice down payment on a replacement car.