Like everything else Amtrak, the answers will be all over the map. Cars will range very good to shopworn depending on cleaning and rehab cycles. Just did a roundtrip to ATL a few weeks ago, Southbound the car was very fresh, Northbound, was clean but shabby. You can be on a packed train one day, and an empty the next. Certain parts of certain routes may be heavily traveled, other stretches (or certain times of year) not so. Think of a Northbound AutoTrain versus a Southbound when the cold weather hits for good. As a general rule, Amtrak coach seats are way better than airline coach seats, on LD trains they are closer to business class or domestic F/C on many airlines, but with more leg room. Since lots of people have trouble sleeping reclined rather than flat, that may or may not matter.