The reason for my question is that I have had mine plugged in since I got it, making it very convenient to just connect at any time. No issues I can tell, but at some point, more likely due to my adjusting some setting in alfaOBD, I lost my auto dimming mirror. I have a thread on that. Nothing seemed to help, so I was stripping out the security bypass cable in preparation of a trip to the dealer to have BCM reprogrammed as a last resort. No other BCM gremlins, just the mirror.
Why do you say you can't leave it in?
Anyway as I was removing it I wondered what real life experience people have had.
To save some of you readers some typing, the reason I didn't just reload my backup file for alfa, was covered in the other thread. I made my backup, went to load it, and it was blank. I was sent a copy of a backup that was very similarly speced, and I checked every single line, resetting anything that I had done. Nothing has worked, so off to give my hard earned to the dealer