My family took the CZ from Emeryville to Denver last summer and we had a great time. It sounds like this will be your first experience in a sleeper. The Standard bedroom is quite comfortable. The seats are almost two feet wide. The space under the seats is a little over 9" tall and quite deep so you can easily store tote bags and stuff out of the way. Just don't exceed the 9" thickness or they'll end up in the way at your feet.
In the nighttime configuration, the room has only about two square feet of floor space. The lower bunk is spacious, the upper one can be a little challenging to climb into the first time. The ceiling clearance does not allow you to sit up, so getting in is a bit counterintuitive. You sort of have to aim your head towards the pillow and roll in on your shoulders. After you learn how its easy, but its best for the smaller person in your party.
I suggest you get one of those toiletry kits you can hang on a coathook. It comes in real handy in the little rest rooms. Also, wear rubber soled shoes you can slip on and off easily (like slip-ons or velcro fasteners) for nighttime toilet runs.
The scenery on the CZ is awesome, especially between Glenwood Springs and Denver. It winds through spectacular narrow canyons that can only be seen by rail or raft. Take lots of film.
You may find, as we did, that the sightseer lounge car was more crowded on the westbound trip than the eastbound. I think that was because those coming off the plains were more starved for scenery than those whe had been in the mountains for a long time.
We found the food ranged from good to excellent, though somewhat inconsistent from day to day. Nothing qualified as bad, however.
One more thing to be prepared for. For a day or so after you get off you may still feel like you are moving on the train. This is perfectly normal, and it will pass.
In our experience we were on board the train about 35 hours each way, but it seemed like less than a day. The ride is relaxing, but far from boring!
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Trust God, love your neighbor, and never mistake opinion for truth.
-Mr. Toy