Bafang G340 series

Does anyone know how these compare to BBS02 and BBS01?

https://www.bafang-e.com/en/oem-area/components/component/motor/mm-g340250cb/
https://www.bafang-e.com/en/oem-area/components/component/motor/mm-g340250350c/
https://www.bafang-e.com/en/oem-area/components/component/motor/mm-g340500c/

Looking at the specs, the only physical difference I could see was weight. Does this mean that it's not only the controller that's changed?
And speaking of the controler, what could be the difference I.e. mosfets?

https://endless-sphere.com/forums/viewtopic.php?f=28&t=96944&p=1420412&hilit=G340#p1420412
Is probably just the BBS02b version. (the original isn't available anymore, the b version has different firmware that causes some issues you can read about in the various BBS02 threads).

So you think all of them are the same? But why do you think the 500 4,3kg and the 250/350 is 3,8kg it has the same outer dimentions?
Also what issues are you referering to? Could you guide me to an example?

I don't know if they are all the same; the only reference I have is the linked thread above.

The issues are covered in various BBS02 threads in this list:
https://endless-sphere.com/forums/search.php?keywords=bbs02*&terms=all&author=&sc=1&sf=titleonly&sr=topics&sk=t&sd=d&st=0&ch=300&t=0&submit=Search