I just picked up a used BMW Zumo 550 to install on a F800gs but am concerned about battery issues. Does anyone know if there are any internal differences between a regular Zumo 550 and a BMW Zumo 550 or their respective cradles? I have read almost all the 550 threads and it seems that when going thru the canbus for power there is a concern that the gps can switch itself back on and drain the bike's battery. In one thread it mentioned the BMW 550 was somehow different besides the connection but didn't explain why. I would think that BMW incorporated a solution specific to the BMW 550 to eliminate the battery drainage issue can someone verify this? Has anyone with a BMW 550 plugged into the canbus had an issue with it draining the battery? I'd prefer to go this route to keep it powered on/off by the key switch if possible.