I like to see these advancements, but I'm in a bit of a quandary, because the parallel development of cheap(ish) rear-facing video dashcams is also in full swing with products like the Cycliq Fly6 and probably others. Right now you either choose radar or video camera, or you will have to mount two fairly large devices at once to get both.
These things really need to converge. I'm a huge Garmin fan so I'd hope they could produce an integrated unit that does Varia radar plus has a looping dashcam video capability, and has the blinking red taillights or whatever. Yeah, battery power, but that's a solvable problem.
I really don't want to have two separate units mounted, and even the standalone RVR315 is large enough that in combination with something like a Fly6 that would be just way too much crap back there.