Nearly all the parts work greatly,but not the standard control power unit (without display).I couldn't set any lower speed or power,even at the lowest settings it speeds up to more than 30 km/h.Therefore the larger battery gives only 20 km of range because of less power from myself.So I got the OLED display which is very good, but expensive.With this I could set a fitting power step and more range.If you have to pay the full price for the set,maybe its a litte bit high.But the battery format is much better than most of these bottle cage batteries of your competitors