Doing this drive however, I am doing it out of Toronto. The routes are not really similar until you get to Savannah. I can easily say with certainty, that if you are in Savannah around 7-8ish at night on your second day of driving, and assuming the weather is ok, I would highly recommend just pushing it to Miami. You should easily be able to make it by 2 am into the Miami area.
The drive is a bit of torture but I gain two things out of the trip. 1) A vacation and 2) 4,000+ AAMiles on my return flight home (I wanted to push my 86,000 miles to 90,000 and found some neat hidden routing flights that were the same price as direct flights, however, from what I understand of the ticket, I can only earn base miles and not Qualifying Miles). Plus, it's worth two days of torture to spend a week at the Fontainebleau pool all day and the spa for an hour everyday in the afternoon.
NOTE: The hidden routing flights I found were only from MIA-YYZ. Mine was a bit extreme and will take 12 hours of flying but I'm doing it for the miles and don't mind wasting the day. I found some even crazier hidden routings that would give you from my estimate well over 7,000 miles if not more (and some would even be qualifying miles) but that would take a whole day of flying.
