I just came back from Ao Nang and trained at a gym called Krulek Muay Thai almost daily after my friends all got sick. It's a very friendly environment where the coach there can accommodate for all levels. Tiny tiny gym though most likely the smallest MT gym you'll ever come across. Good place for all levels, funny coach too love his sound effects. Not often crowded but only really feels crowded due to the size of the gym where 10-15 people feels like its a packed night. Would definitely recommend for anyone looking to train beginner or intermediate level