I just bought a 70mai pro plus+ A500S and I found that emergency recording doesn't start. I shake the whole car with the help of a friend and still no emergency recording starts. I have to literally tap on the camera itself to make emergency recording start. I think the sensor on this is very very low.
I also have an older version of the dashcam 70mai smart dashcam pro and it works really well. the sensor on it is very good, the emergency recording starts even when I just open or close the car's door.