The fire hazard from the cheap breaker is still present. Your existing one protects the downstream circuit but the Chinese breaker itself is a safety hazard.
You should care about the quality of these devices, especially ones that provide safety.
Just a nit: The Chinese breaker isn't providing safety. You should still be caring about its quality because it's handling a lot of current (and potential power).
You should care about the quality of these devices, especially ones that provide safety.