I've done the autotrain once, and thought coach would be just fine since I can sleep anywhere. Boy, was I wrong! I spent the entire night waking up every time anyone went by the seat. And this was an uncrowded train where I had the entire row for me. I wasn't/couldn't get comfortable at all. Coming home, I upgraded to a standard sleeper, and it worked much better, though it was really small. Travelled by train as a kid, and had forgotten that the romantic "rhythm of the rails" is just that....romanticized. Train travel is NOT a smooth ride. My daughter, in the upper bunk, thought what she was going to get thrown out!
On the positive side....it's a whole lot better to drive for 2 or so hours to get to Disney World than the alternative! And it's nice to have your own car while there. My son is in school in Tampa, and will be riding the autotrain lots over the next couple of years. His last trip, down to school in August was a disaster. From the crowded car, the crying kids, the late-night talkers, the couple behind him that REALLY should have booked a bedroom, and the emergency stop caused by running over a fallen off cargo door, he's not looking forward to his next trip in December! He'd rather drive, but Mom and Dad (the source of all money) say no because of potential bad weather. He's a Floridian at heart, already, and doesn't factor snow and ice into things anymore.
Chris in Md.