I have seen people bashing the dual battery setup which does contain a CTEK it seems. I also recall (but I kinda pushed it out of my mind since I could not check one anyway) that some youtubers blatently seem to misrepresent the system, some thing like "they are both connected continually." which seems a very strange thing.
It can always be upgraded as long as you do it properly.
Cheers,
-P

