I have volunteer with them for 2 months, and this is my impresion:
Very disapoining experience. There were a coulpe of vietnamese workers who were helpful, but the rest of the team were distant and unsocial. they lie to me about having breakfast, very disorganiced (you dont know what you have to do, for hours, until last 5 minutes before the class) they didnt tell me any activities to do in the city so I was bored 20
hours a day, they locked the princial door with me inside more than once and the list of problems continue...