we drove last march from Nothern Ontario... we live about 3.5hrs from Toronto. IT WAS LONG. Really long and you do need to stop unless you are switching drivers. We had to stop two nights and the first two days was 12hrs days, the third was 7/8hr day. We stayed for two weeks. I think driving all that way for 3 days is too much. The drive itself was ok on the way down but the weather was horrible on the way back. Atlanta driving is NUTS, and the Mountains of Tennesse were sooooo FOGGY on the way back because of bad weather. It was scary. But like I said the drive down was clear and nice. The way back there was storms in Florida and everywhere else and once we finally hit Canada it was snow storms.
The hotels on the way down were easy enough to get but the way back were all booked and we ended up staying in Motel 6 that was HORRIBLE. The Hampton Hotel was very nice. If you have CAA card you can use it at all the hotels and get a pretty good discount.
I 75 highway is the way to go. (straight drive, no getting lost)
DON"T stay in a MOtel 6 whatever you do!! DISGUSTING.
We did have a wonderful trip. On the way home I did read three books haha! Because I was freaked out watching the road.
We also took two vehicles. Our Envoy SUV and my mom's Van (we had 5 kids, dh me my friend's Step daughter who was 20 at the time and my oldest son who was 19yrs old.