Tianjin brand, I am from Tianjin, and I also make bicycles.
This brand is good and the factory is quite large. There won’t be much problem with the quality, but there is no advantage in terms of price. The kits for electric cars are all patented, so the parts for the same car often come from the same place, but they are put on different brands during assembly. It's just decals, so the quality difference isn't very big, just look at the main components, such as batteries and motors.
The main thing to ask about the battery is how long it will last. For big brands such as Chaowei, Fengfan, Huafu, etc., it is recommended to buy gel ones, which have obvious effects in winter.
Motors generally get what you pay for. For big brands like Anida and Omar, try to choose brushless motors because they have high horsepower and are maintenance-free. Brushed motors require replacement of carbon brushes. However, a motor with greater horsepower will do more damage to the battery, and generating large current will damage the battery life.