we have driven twice, and are driving again this fall. The closest major airport is 3 hours away, so any flight would also include a hotel stay. We have priced it out several times, and found flying, after taxes, etc, much more expensive. We pack snacks for the first day, and eat breakfast at the hotel, so the 'additional' meals aren't a big deal.
We spent $250 on gas, $200 on hotels, and $100 on food.
Tickets to fly, were $800 (incl. taxes), a hotel the night before $120. $40 for meals, and $40 for gas.
$450 less, and we don't have to rent a car.
I also enjoy the drive. As far as times. To fly out of Buffalo in the morning, we have to leave here the evening before, and arrive in Florida around noon the second day. When we drive, we leave early in the morning, and arrive at Disney, shortly after lunch on the second day. We sacrifice half a day, on the first day. As far as mileage, the difference in vehicle value for a car with 120 000 km compared to one with 145 000 is minimal.