It's plug in and removal and can be turned off without removing so no one would know.. I can't see how anyone would even know it's fitted if turned off. It works by injecting commands into the canbus the same as a switch, so if turned off the canbus just bypasses it..
I'm reasonably happy with the positon, mileage may vary though.
UPDATE - Right I've now had the V2 instaleld for a few weeks and it's worked perfectly. It has an app and you cna confirgure what you want on and off. The unit can be turned off witht he cancel button and overall brilliant. Mine turns off lane assit speed alert etc .
I'm not sponsored or linked to B-Tech who make it but did have their Mk1 which had a few bugs the V2 is sorted. You do need to be reasonably DIY to fit as it requires some trim/dash removal but having done it twice now I'd say I coudl do it in 15mins.