The 110 cm version is a good choice, because you need a certain length to be able to attach the bike to a post or similar. Another advantage is that the Bordo 6500/110 is very compact when folded up for riding. However, given the thickness of the links, it's less manoeuvrable than a cable.
I don't see the possibility of using the same ABUS key as the one supplied with the electric bike. Probably only ABUS could answer your question.