Personally, I prefer to drive if I have the time. The airport is more stressful and unpredictable for me. On this last flight, we ended up having problems yet again with delayed flights and a stressful transfer where there was a high chance of having to spend the night in Detroit. Meanwhile, MMM drove, met a bunch of great people, experienced some new cities, and had a great time. If you're driving with someone, it's a great time to talk and really connect with someone.
But with a kid, it's sometimes easier to just get there faster, but overall, I prefer to drive when traveling.
I think it's better Environmentally too, but I'm not sure...