They can be a nightmare but better to try and keep it in because it may not pass an MOT. Plenty of other things can begin to go wrong when removing it, mainly the software. It ends up going on a loop to try and find it and sometimes the immobiliser kicks in. I used to go a long drive once a week until I read about small metal discs that go into the diesel tank. Bought them for £40 for five and haven't had any issues since and that was years ago. Mike Brewer was advertising them, I thought it was a con but they worked for me.