I have traveled between Yangshou & Shenzhen several times & every trip has been pleasant. My inability to sleep is my problem not the bus’s fault.
Being a non speaker of Mandarin I seldom get to discuss buses with agents in Yangshuo who rarely speak more than basic English. So I buy a ticket at a suitable price. However some people get the phone numbers of drivers & arrange pickup by phone. The ticket cost is a lot cheaper this way. But to catch one of these buses you need to have a Chinese person with you to communicate with the driver for pick up.
The buses to Shenzhen leave from Guilin where passengers are required to go through the ticket checking process. However in Yangshou this does not happen as the buses will stop somewhere on the roadside or even the bus station. By paying money direct to the bus staff, passengers get a cheaper fare. This way the fare to Shenzhen can be as little as 100y, but a return trip where you have to go through the ticket checks, it costs up to 250y depending on what time the bus leaves. A bus to Yangshuo leaves from Yinhu bus station in Shenzhen. During holiday times the bus is more expensive & tickets are harder to buy.
I always travel by overnight sleeper bus. If I can get a top bunk bed in the front behind the driver (there are three rows) I am delighted as there is nothing over my feet. I am tall with big feet so extra foot room is welcome. The shorter Chinese can store their handbags where I struggle to put my feet. The beds of course are narrow, but OK. However sometimes the pillows offered are not comfortable & probably dirty too. Once I had a silk covered pillow that slipped everywhere it was not needed. I now take my own small pillow which makes a big difference. (It’s a baby pillow.) I usually find the velour blankets they supply are too hot. But without them on, it’s too cold. It all depends on what temperature the driver chooses to use. It’s too inconvenient to take a blanket too. Seat belts are on every bed, but they are rarely used. They are very inconvenient when trying to turn over.
There are many buses available during the evening. Overnight buses pass through Yangshou between 7.30-10.30 pm. The trip, if all goes well, can be done in about 10 hrs. This includes toilet & a meal stops. The earlier the bus leaves the earlier you will arrive at your destination. Maybe it’s not convenient to arrive too early in the morning.
Many take food on the bus with them, but there is hot food available at the meal stop. Depending on the season, there is often fresh fruit for sale
Some buses carry freight so the luggage area is full, resulting in all passenger bags having to be put somewhere inside the bus. Of course the obvious place is the aisles. When trying to alight at rest stops there is no choice but to walk over the luggage
Shoes are not allowed to be worn on the bus. As passengers get on the bus they are handed a plastic bag where shoes are to be stored. This is a very strict policy & watched very closely by the driver. But rarely do passengers care about their plastic bags when they get off so they are dropped on the ground & new ones used when they get back on the bus. This is so annoying to me, an ardent environmentalist.
There are always two drivers. The one initially not driving takes care of getting passengers & luggage on board & collecting money. He checks passenger destinations so the driver knows ahead of time where his stops will be. There is bed space for the 2nd driver as they need to sleep. Sometime during the trip the co-driver goes through the bus giving each passenger a business card. These cards contain many phone numbers, but basically they are drumming up future business for their bus. A full bus is a profitable trip.
For me catching a bus in Yangshou is very convenient. Yangshou is a small town so catching a bus is barely five minutes from anywhere. Sometimes I have been able to get the driver to drop me off outside my home on my return.
To go by train is more expensive & time consuming. First you have to travel to Guilin by local bus, 1.5hrs. The trip to Shenzhen is a little longer & tickets more expensive than the bus. There is only one train. However on the plus side it’s more reliable than the bus. Anything can go wrong on a bus trip. Most of my trips have been uneventful except for one trip when the bus was at least six hours overdue. No one thing went wrong, just a series of things from traffic snarls to some minor bus repairs.