Mercedes' Distronic uses a radar unit up front (not laser), and it is constantly on, independent of whether the system is activated or not. The Distronic in my CL used to warn me of possible dangerous situations that may have caused a collision. It used that radar unit to do this, and it was on, always.
I am not aware of it causing any problems with detectors, but I didn't ever really check either. My car had both Distronic and Parktronic, so if any of that screws with a V1, I supposed my car should have. But Parktronic has a very short range... 5-6 feet. Distronic radar goes MUCH further... 300 feet easy.
On a few occasions the system would beep and flash and there I was, headed towards something and not paying attention. I don't know how the car knew I was being stupid, but it did. I sure miss those features now.