It only goes from Lorton, VA to Sanford, FL. It takes a long time, it's not cheap.
My in-laws tried it about 20 years ago. They drove from MA to our house, a short drive to Lorton. At the time they were spending 6 months in FL and 6 in MA. It worked ok for that kind of migration, but not so great for a short term trip, maybe just once out of curiosity.