Not a cheap Chinese e bike but my KHS fatbike that has a Bafang BBSHD 1000 watt mid drive has been ultra reliable for 6 years now. It gets used in weather down to minus 20C in winter and in summer. I am retired so it's use is occasional and in summer the delta trike see's more use. One mechanical breakdown in 2020, the rear freehub broke, so I took the wheel off and took it to the LBS for repair. It has approx 4,000km's now and I'm going to replace the chain and have the cover off to grease the big gear.