In first class, seats were two abreast with soft cushions, tray tables in the arm rests and plenty of recline. Somewhat similar to a US domestic first class product.
There was plenty of leg room for a tall guy like me (6'2").
If needed, there was an electrical outlet near the floor at the back of the seat in front of you. I thought the placement of the outlet was somewhat inconvenient as it means you need to run your cable along the length of your legs to your laptop or iPad which means you or the passenger seated next to you might trip over it.
There is overhead space for carry-on bags, while large bags can be stored in a closet near the entrance doors to the carriage.
Soon after departure, we were served a snack box that looked very healthy and promising...
... but contained just some crackers, spicy raisins and some bread.
Around lunch time, I got another one of these snack boxes for free although I am not sure if that was a mistake. Beforehand, I was under the impression that you only get served once.
The train ride itself was rather unremarkable. For about 5 and a half hours we passed mostly grasslands shrouded in mist and grey clouds due to severe pollution that day. Also, the first class section was rather empty leaving from Xi'an until the first few stops along the way. However, closer to Beijing almost all seats were taken.
After arriving in Beijing West train station, I walked to Taxi cue #3 and waiting for about an hour in line until a taxi showed up to take me to my hotel.