Terminal 21 is my favorite mall in Bangkok - it's nice to see Pattaya getting one. The location is easy to access since it is along the baht bus routes. There is a plane outside on display, which Bangkok doesn't have. The interior with the giant escalator is similar to Bangkok and the flight/travel theme present. The food court is great too, just like the Bangkok location. Not as many stores, but plenty to walk around and browse. Good way to spend some time out of the heat and a great place to get something to eat.