The torque sensor in the tongsheng makes the battery go further with less perceived effort and is just generally nicer to use. Hitting 25km/h feels like less of a wall.
I can go 75–90km on one charge with the open source firmware and a 850Wh battery. And you can service the bike yourself because it’s all standard parts (and you had to put it together yourself in the first place!)
You can also use any generic battery or build your own.
You can also use any generic battery or build your own.