Does aftermarket video interface really allow video in motion?

[colh]

I've been looking at a couple of the video interface adapters for COMAND 2.0 on ebay, which claim to allow video whilst in motion.
Is this really possible? I had assumed that it was the COMAND itselfl which shut off the video based on speed input. Or, if such an interface is wired in on such a way as to 'interfere' with the speed input - is that going to mess up the GPS? (e.g. in a tunnel).

 

[markmifsud]

The interface I had deff did work in motion. It had no adverse affects on any other part of the system