Testing sounds interesting, if still at prototype stage. Couple of years away from release but shows the way industry is moving after TQ, Fazua 60 etc. Smaller, lighter and able to use third party crankset so Q Factor is same as ordinary bike.
Good in-depth article here:
road.cc
Good in-depth article here:

Mavic superlight X-Tend e-bike motor system fist ride: an e-road revolution?
Mavic's new compact motor weighs just 1.2kg, in a break with tradition from the legendary wheel and component specialists