this one is much better designed and much more sophisticated than the friction drive stuff discussed on ES.
Using the bottom bracket to mount the friction kit is inspired.
It has a pedelec sensor and properly unloads from the tyres when you stop pedalling.
It solves one big problem with converting bikes fitted with hydraulic brakes.
and it's also easy to scale up in speed and power.
If I were Bosch, I'd buy these guys out rightaway,