Used bulls, good buy?

[siltsunrise]

Hi are all bulls green mover motors indeed swissdrive motors? Any difference between them and stock swissdrives?
Have they evolved much since 2011? I'm looking at some used bulls bikes and don't know if any year models are better or worse than any others.
Any issues with any other parts of the bulls green mover package - controller/display/battery, etc?
Thanks