Yea, looks like they do only custom bikes for mostly heavy duty applications. One of them looks like it's made to transport sheets of glass for example, looks like a lot of their business is building custom bikes for craftspeople that need to transport more than a few groceries. They are definitely heavier than a normal cargo bike, but you'll probably not notice much of a difference thanks to the whole electric pedal support (as far as I know only speed is regulated, not torque or acceleration, so this thing will easily get to and cruise at about 25 km/h just like a lighter cargo bike will)