It is much easier packing for a trip by car. When flying, you rethink every item -- is this something I really need? -- trying to get it down to the minimum necessary. In the car, it's the other way around -- is this something I might need? Throw it in!
The time factor is very different as well. The plane doesn't care if you're there or not, so the morning of a trip by plane, I'm watching the clock closely, planning carefully what needs to get done so that I get out of the house on time. Last night, when I asked Lynn what time she wanted to leave, she said, "About 10:00." That means anywhere between 10:00 and 11:00. No pressure.
It should be sunny between here and Biloxi. Most of the drive is on the interstate, so it'll be boring as hell. But it'll be pretty on the Gulf, despite the casinos. The temperature there is still in the upper eighties.