As far as my own learning experience is concerned, easy learning is good, and the teacher's pronunciation is quite standard. The open class you saw should be Mr Jason, who came back from America and knew Mandarin there very well. But I prefer female teachers who are easy to learn. . . Haha, the level of female teachers is also very good. My class is taught by Vera. I like her class very much. Super funny. I haven't taken a class in VIPABC, so I can't compare with it. After all, the price here is cheaper and more cost-effective. VIPABC is too expensive.