I just bought the same device.
I already have an Rfxcom reciever and a number of other 433 MHz devices, among wich a couple of door switches. I didn’t buy a Sonoff bridge because I assumed the Rfxcom would be able to handle it.
But it doesn’t see it.
I notice in Rxcfom configuration that all protocols were unchecked. Is this correct? All other 433 devices still work like a charm.