Traveling with infants

Hey guys I was wondering if anyone has traveled long distance with an infant. Is it easier flying or driving? I’m torn I feel like both would be beneficial, we’re traveling to Florida which would be about a 2 hour flight and a 12 hour drive. My grandparents said they would go out and buy whatever we couldn’t take on the plane for the baby but I feel like that’s pointless for a week trip when we could pack the car up but at the same time a 12 hour car ride seems like a lot for an infant so any opinions ??