We took a day time sleeper bus with HM Happycar from Hoi An to Phong Nha. I received a WhatsApp message from the organizer to ensure we found the bus ok before departing. The bus was extremely clean and in great condition. The little bed capsules were private and lay totally flat, or you could put them into a partially reclined position. I am 5'4" and could lay completely stretched out, my friend is 5'9" and could do the same with flexed feet. There was a USB port, lights and air vents. The driving felt very safe and there were two drivers who traded off which helped us feel safe as well. We stopped 3 times for toilet breaks. After getting dropped off and going about our day, we realized we forgot air buds on the bus. I messaged them via WhatsApp and they responded immediately that they would ask their cleaning staff. They found them and organised a nearby hostel for them to be dropped off at for us to pick up at our convenience. Very impressed overall, would book with them again.

The first time I went from Nghe An to Da Nang, I was a bit worried that the bus company was cheating me, but in reality it was very ok. The bus company was friendly, the operator called to confirm and remind me of the schedule to avoid missing the bus. 10 minutes before the bus arrived, both the driver and the operator called. All information about the license plate and the driver's phone number matched the email received. I kept the seat I booked for myself. The bed was spacious and comfortable, the bus ran smoothly and had no smell, and I arrived in Da Nang almost 1 hour earlier than the scheduled time. 10 points, next time I need to choose this bus company to go from Vinh <-> Da Nang