Each day, the train made two 20-minute stops. You were allowed out of the train, but only to the platform area. Still, it was quite a treat to get some fresh air, walk around, and buy food from the vendors (if available). That was another thing--food. Although I was glad to have brought 6 days worth of provisions, it was comprised mainly of processed food. Breakfast: instant oatmeal. Lunch: instant soup and a piece of fruit. Snack: Popcorn and a candy bar. Dinner: instant noodles. (There was always hot water available.) Relying on the dining car or platform food vendors would not have been reliable. The hours of the dining car were unpredictable and involved walking through five carriages, with four doors between each carriage. As for the platform vendors, I managed to buy tomatoes, carrots, ground meat patties, potato dumplings, grilled chicken, and cheese, but you never knew when the train would stop and what the choices were.
Seeing that I had no one to talk to (up till the fifth day), how did I spend my time on the train? The Lonely Planet cites "War and Peace" as a popular choice among travelers on this route. I opted for "Harry Potter and the Half-Blooded Prince." I averaged about 8 hours of reading per day, with naps every couple of hours. (The beds were acceptable--linen, pillows, a blanket, and lumpy padding were provided. I was warm enough and short enough, since I still had 3 whole extra inches from my head to the wall.) I also broke up the day by looking out the window and watching the scenery go by. In addition, I placed a lot of importance in cleanliness (making my bed, washing my dishes), but personal hygiene was another matter. There were no showers on the train, but the bathrooms were pretty decent. Although I didn't bathe for the whole journey, I managed to hastily wash my hair twice (by standing over the toilet and dumping water over my head with my cereal bowl). But seeing that I didn't sweat much by reading and napping, I thought my BO was under reasonable control.
All in all, I'd highly recommend this journey to anyone who enjoys confined spaces, is on a preservative-only diet, thinks personal hygiene is overrated, and has a lot of time on their hands.