I can actually add some weight to this.
I had police ask if they could speak to me. Because someone I used to associate with, who had seen the RIFs in my home had informed them that I had some kind of firearm. Two non armed police officers came to my door, no warrant, and politely explained and asked if they could see said firearm. Upon discovering it was a RIF they chuckled, had no further questions, didn't ask for a defence and simply left.