Are there any good rearview mirror reversing cameras?

I own a Toyota RAV4 which has a factory sat nav and an automatic dimming driving mirror. I would like a reversing camera but have been told there is no interface available to connect to the existing head unit, therefore, a new head unit and wiring etc is not cost effective. I believe the only viable option is a mirror unit and would welcome recommendations for a suitable system that I can have hard wired. I have seen several systems that are WiFi and wonder if you have recommendations?
We haven't tested any reversing cameras so unfortunately, we can't offer you any advice in that respect. There are lots of dodgy reversing cams around online, so beware of reviews and ratings on sites like Amazon. Auto-Vox are a known brand to us because they also make dash cams, and they're reversing cam is well rated by 290 people on Amazon, so this would be our best bet:

They also do a mirror unit, but there are two issues with this. Firstly, these can be difficult to hardwire, it definitely isn't a job you can do yourself - the wires often need looped through the rear lights so the entire light cluster might need removing for fitting. Secondly, we don't personally advise using mirror units because they aren't big enough to see things clearly. An infotainment screen where reversing cameras are supposed to link through are large enough to see things behind the car properly, a mirror isn't in my opinion. You could always opt for something like a FenSens unit. We reviewed it here:
Answered by Georgia Petrie on

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