i am using c900 for 1 month already, so far so good. Caught someone on tape for traffic violation.
operation is fully automatic. When you start the key, the cam starts recording. ignition off, cam off. No need to worry battery drain in case forgot to turn off.
when security record mode is selected, if someone walks by will activate the recording.
the recorder will be powered from internal Li-ion battery. It will stop recording until the person go away.
Recorder will recharge itself once you start your engine.
The chipset and controller are made in taiwan, assemble in SZ. I think it worth a try for just RMB268.
I posted the link before under this thread, so I dont plan to give again.