As you may know, I'm new to train travel, having taken only 5 long distance trips* (but all in 6 months! Does that count???). The thought of a long trip in coach has no appeal to me, and I'll never, ever do it. But, yeah, I can see how even seven hours becomes "too long", and the ability to snooze, stretch and relax can really be worth it. We returned from New Orleans Friday PM, and I had to drive 100 miles yesterday (each way) to pick up our pets who were being babysat by our daughter. Four hours in the car, and when I got home, I was beat. More beat than I was after a 19 hour ride in a bedroom.
I wonder what my threshold would be for wanting a sleeper - even if I didn't sleep!
*excluding the 1955 NYC trip that was in a wreck, killing the engineer.