I've had the pork belly baos at Mean bao twice - they are delicious and one of my favourite pork belly baos in the city. The pork belly is juicy and flavoured while the bao is soft and fluffy. On one of my visits, I tried the dim sum which was a mistake - stick with the baos!
Mean bao is hip and gives off that "hole in the wall" vibe. However, the seating inside is very limited. If you come with a big group, consider sitting outside during the summer.