Est 16 hours, 40 min. Adding stopping for gas and one of the girls will have to stop for the bathroom fairly often, I suspect, I'm actually thinking it'll run us closer to 18 and 40 min. I'm more of the type to load and go, no stopping unless neccessary, but... not all my girl friends like traveling like that.

I do think we're going to stop once we're in FL and hit a beach in the morning. Another girl friend coming along has never been to a beach before. So, I figure some nice, white sand beaches and clear water would be a good visit for her.
And I do alright with the truckers - years of driving with them from college. I'll just miss having a CB to talk to them!
Fun part is, they don't read maps, and one hates driving. So... I'm the navigator. I mentioned that if I needed to come back home early for emergency, I was going to have some $$ set aside for a quick flight. The other driver panicked.
Asked how they would get home.. um.. car we came in? Well, but how will we know how to... um.. same way we came? But, we might get lost! 
I'm taking a GPS for them. Don't do well with those myself - tend to get annoyed when they keep telling me how to drive and where to turn. But, I expect they'll like it a great deal.
It will be a REALLY fun drive, though. Lots of Disney songs played and perhaps a DVD or two watched while en route.