Yes - I took the Trans-Manchurian early last year.
Meet strange people, eat too much omul, drink too much konyak (hint: it doubles as drain-cleaner), have torturous conversations with people who only share six words of vocabulary with you, get extremely
disoriented by the timetable and timezone changes, catch a serious gastrointestinal illness from the canteen car, don't shower for a week, read too many books, try writing and give up after a day, despair when your walkman runs out of batteries and you're 1000 miles from the nearest replacement, slowly go mad without any GSM coverage for days on end, take thousands of photos, learn things that you never wanted to know from the provodnik(tsa) every time you go to the water-boiler, learn the kind of Russian that you'd never learn in school, watch thousands of km of birch forest and wilderness and mountains and rivers roll past...
It's excellent; a very interesting holiday. I loved it.
However, I don't really want to travel the same route for my next holiday... It's a huge world; why go to the same place twice? According to Lonely Planet, the Torugart Pass is one of the world's most difficult border crossings, so I'd like to try that route across Asia next time.
The Russia-China border crossing on the Trans-Manchurian can be a little stressful; there are several bits of ominous-looking paperwork to deal with, and nobody's is perfect. Anyway, you'll probably share a carriage with some Chinese/Russians trying to carry illicit goods/currency across the border; they have more to worry about, and their nerves are contagious when you're trapped in a carriage with them rolling along the very slow, very barren approach to the border.
The train stopped at certain places and you were able to get off and spend the night somewhere on land as i recall
For most tourists, this would be an extra-cost option arranged with the travel agency.
Mongolia is where people normally load up on options (jeep trekking, spend 2 nights in a ger, &c &c), and you could tick an extra country off your list if that's what you're interested in - the trans-Mongolian is a slightly more mainstream tourist option. It'll also cost slightly more (mongolian visa; currency changes) but is slightly faster than the trans-Manchurian simply because it takes a more direct route.
The actual journey costs - your train ticket and a few days of food - are very low. The vast majority of your money will sink into hotels at each end, flights, visas, and of course the travel agency markup.
...a (cute, female) coworker is trying to round up people to accompany her on a Moscow to Beijing trip on the Trans-Mandchurina train. The trip is supposed to last five days...has anybody here undertaken such a trip ?
Yes; go. Don't think twice. Book it, you won't regret it.
When is she planning to travel? Summer and winter are very
different experiences. Also, what class? 1st / 2nd / platskartny? Does she want to break the route, or do it all in one journey?