Electric Motorcycles & Electric Bicycles

Regarding Bosch, you've said it perfectly. Chinese kits, on the other hand, are recommended for all applications. Almost everything has been standardized (copied) and can be used interchangeably. There are 10+ factories that make compatible motors, 10+ factories that make compatible batteries (actually just + and - on a standardized and inexpensive connector), 10+ factories that make compatible controllers, and so on. You have complete control on the type of bicycle you get. Read a full guide here.

Yes, so the buyer definitely has to be careful and read many reviews before the purchase or they may get duped into thinking that it is more than they are expecting, especially when they compare it to more expensive bikes.

For some people, its price only and couldn't care less about quality until it breaks repeatedly. Only then does quality become a consideration. But depending on the expectations, 'good enough' at the cheaper price may be enough.

Like many types of bike riders, expectations can also be graduated along with experience which I think is both healthy and normal. For an amateur to buy top quality and use it once is pointless, unless that person has deep pockets.

Like many things, the usage model should be the first consideration and the experience second as in time the risk of paying too much vs getting-what-you-pay-for is a harmonic balance.