@InRustWeTrust Right, the Teewing question. From my search, I can see Teewing has no previous experience in building mountain bikes, but does sell a range of electric scooters as well as a carbon folding bike. However, their parent company, Shenzhen Teewing Industrial Co, has been in operation since 2014.
The bike industry is absolutely full of brands using ODM (original design manufacturer) frames from Chinese factories. This is completely normal. Chinese companies have their own products with their own brands now: Lewis, Wheeltop, Ztto, Quickpro, Amflow, Teewing, etc. The bike industry isn't ready for the incoming wave of Chinese products that are actually good.
What makes Teewing different from an AliExpress frame flip is they're actually manufacturing and selling complete bikes with proper support networks. They've confirmed their bikes conform to the "500W continuous power output" max requirement and all bikes coming into Canada will be restricted to 32 kph max speed, which is also the requirement in most locations to be viewed as a road-legal power assisted bicycle.
The reality is that most bike brands use Chinese manufacturing. The difference is in quality control, R&D investment, and aftermarket support. Teewing appears to be positioning itself as a proper brand rather than just slapping logos on generic frames.
From what I can see, they're building around the DJI Avinox motor system with proper engineering rather than just mounting components to random frames. That said, they're still very new to the MTB game, so buyer beware on long-term support.