My ebike with a Bosch drive unit and a 400 Wh battery gets me a range of about 35-40 km on the maximum assist mode ("Turbo").
Also, the batteries are easily swappable. Just place some chargers with extra batteries in a few of the restaurants...
I had to crack the 25 km/h speed limit restriction as going above it required an almost Herculean effort. It should have reverted to an assistance level that offset the weight / drag, but alas.. it just turned off.
Batteries were easy enough to replace though.
What I like the most about this is the sensor system. I am pretty sure there is an actual torque sensor in there. This makes for a very smooth acceleration phase.
Along with a back wheel magnet sensor to keep the speed limit. Last year I made a homemade hack for this.. I used a microcontroller, an electromagnet and a magnetic sensor from a cheapo bike computer to forget every second impulse towards the Bosch system. It worked. The speed limit changed to 50 km/h.
Ended up not bothering to weather-proof it though. 25 km/h is enough most of the time anyway.