Basically, for Dual Drive on a MP II, you are able to configure the regen braking with the Computer Interface. I've been receiving reports about the Dual Drive with the MP I that the regen braking is TOO strong and grabby. Hence, with the MP II, you can test ride it first and decide how much regen braking you want, as well as the Peak Current, which supposedly controls the acceleration.
For me, my Dual Drive MP II was made for a top speed of 45KPH on a 48V, because my bike frame wouldn't be handle speeds higher than that. There will be a custom option in the new Order page when the MP II comes out, and you can choose to custom make the RPM to higher speeds. On a 72V, it can be made to be at 100KPH, but that will empty your battery really fast. Seriously, the point of Dual Drive is just to show off. Or if you have a 20AH battery, then perhaps you can use it for long distance transport.