It's a loud train and felt incredibly disgusting. I took another train with another company after and it was much better.
While the toilet was being cleaned throughout the nice, it didn't feel clean at all at any stage.
That said, the welcoming thing was the view and the boiling water tap, which allowed me to heat some noodles I purchased at the train station.
The bed was firm and the train was loud and rickety so please bring ear plugs.
Train has a shake but rest everything is perfect. It has a restaurant compartment for food. 12go is not supporting some international debit cards like Niyo DCB. It shows declined but it is working in other booking sites.
We travelled 2nd class but would have gone 1st if I had my time again. The beds were pretty hard but ok. The trip started pretty quiet but got busy and loud at Na Trang. Slept ok and glad we did it but all in all a bit rough
All in all, a pleasant experience. We were lucky with the neighbors in the compartment. The views from the window were amazing. Cockroaches ran from time to time (but this is Asia, what do you expect). I doubted the cleanliness of bed linen (namely pillowcases and blankets). Due to the AC it was quite cold. Toilet and other stuff was ok for the train. The only thing was that it was quite difficult to sleep, as it shaked very strongly all the time.
Excellent train. We travelled on SE2 (one of the newer trains - check ‘the man in seat 61’ website for an explanation of Vietnamese trains). I read some other reviews, including bad ones about the state of the trains. Our cabin was very clean, the restaurant car was a nice place to sit and watch the world go by, the toilet smelled but you’re on a train - what can you really expect? We could not smell it in the carriage. The staff were helpful. The bedding was clean and the people we shared a cabin with slept the whole time. You have a little light and charging point at the head of the bed. My partner is almost 2m tall and he fit in the bed laying flat out. There was ample room for luggage above the door to the cabin. Vietnam have excellent trains considering where you are, much better than a coach for sure!