I am not sure of the product you identified. However, I used a plug an play unit on my 2006 Prius. It just handled the Nav while you are moving. What happens is that the car thinks it stationary. But after about 30 seconds it realizes that the car is in a different location. So the screen adjusts. You don't lose what you already put into the system. You can then continue until all info is in. So yes they do work. I paid about $100 but it did not do anything for the phone. For that I just disconnected a wire and set up a switch that I could turn on and off. I am looking for something similar for the Rav4 EV. I just got one Friday. I will keep you posted.
Manny